Answer:
B) $16
Step-by-step explanation
A student performed the following steps to find the solution to the equation
X2 - 2x - 8 = 0. Where did the student go wrong?
Step 1. Factor the polynomial into (x - 4) and (x - 2)
Step 2. X-4 = 0 and x - 2 = 0
Step 3. x = 4 and x = 2
A. in Step 2
B. in Step 1
C. The student did not make any mistakes, the solution is correct
D. in Step 3
Answer:(b) step 1
Step-by-step explanation:
The wrong step in the student's workings is step 1
How to determine the wrong step?The equation is given as:
x^2 - 2x - 8 = 0
Expand the equation
x^2 + 2x - 4x - 8 = 0
Factorize the equation
x(x + 2)- 4(x + 2)
Factor out x + 2
(x - 4)(x + 2) = 0
The above means that the factored equation of x^2 - 2x - 8 = 0 is (x - 4)(x + 2) = 0
This means that the step 1 of the student's step is wrong and incorrect
Read more about equations at:
https://brainly.com/question/2972832
#SPJ9
Lauren has a bag containing 6 red, 8 blue, 5 green, 9 yellow, and 2 white marbles that are all the same size and shape. What is the probability or randomly choosing a white marble on the first pick, not replacing it, and then randomly choosing a green marble on the second pick?
Answer:
can someone give us the answer if its independent or dependent
Step-by-step explanation:
George has 52 coins in quarters and nickels. He has a total of $3.60. How many quarters does he have?
there are 36 quarters.
Let the number of nickels be x
Let the number of quarters be y
Value Value
Type Number of of
of of EACH ALL
coin coins coin coins
-------------------------------------------
nickels x $0.05 $0.05x
quarters y $0.25 $0.25y
-------------------------------------------
TOTALS 52 ----- $3.60
The first equation comes from the second column.
x + y = 11
The second equation comes from the last column.
0.05x + 0.25y = 3.60
Get rid of decimals by multiplying every term by 100:
5x + 25y = 360
So we have the system of equations:
x+y=52
5x+25y=360
We solve by substitution. Solve the first equation for y:
x + y = 52
y = 52 - x
Substitute (52 - x) for y in 5x + 25y = 360
5x + 25(52 - x) = 360
5x + 1300 - 25x = 360
-20x + 1300 = 360
-20x = -940
x = = 5 the number of nickels.
Substitute in y = 52 - x
y = 52 - (5
y = 47 quarters.
The number of quarters is 52-x or 52-5 or 47 quarters.
If you want to show an increase to the original quantity, how could you change the bar diagram?
Answer:
Write a situation in which positive and negative numbers are used to describe values that have opposite meaning. What does 0 represent in this situation you created?
Step-by-step explanation:
What is the solution for 3x =9
x = 3
Divide each term by 3 and simplify.
HELP PLZZZZZ AS SOON AS POSSIBLE GEOMETRY WITH EXPLANATION
Answer:
34.06°
Step-by-step explanation:
25 is the length of the hypotenuse side and 14 is the length of the opposite side.
Therefore, you will need to use sine to work out the missing angle.
sinx = opp / hyp
sinx = 14 / 25
x = sin ^ -1 (14 / 25)
= 34.06°
There were 45 runners to start a race. In the first half of the race 2/3 of them dropped out. In the second half 2/5 of the remaining runners dropped out. How many runners finished the race?
Answer:
18 racers finished.
Step-by-step explanation:
In the first half, 30 racers dropped out, because 2/3 of 45 is 30. In the 2nd half, 12 racers dropped out, because that is 2/5 of 30. So, in the end, 18 racers finished. (I might have done this wrong i did my best)
please help. i will mark brainliest for whoever is correct.
Answer:d) g(x)=x^1/3-1.5
Step-by-step explanation:
PLEASE HELP!! (Look at the picture)
Help with the whole thing please and thanks
1a. closest to 1
b. closest to 0
2a. closest to 1
b. closest to 1/2
Numb 3. Ain't clear.
4. Not sure.
5a. closer to 1
b.closer to 1/2
c. 3/4 - 5/12 = 1/3
6. 26/15
7. 7/18
8. 47/240
9. 191/225
10. 11/60
11. 81/200
I really need help for this geometry question, I would appreciate any help thank you.
Answer:
hypotenuse = 4.24
Step-by-step explanation:
sin θ = opposite / hypotenuse
sin 45 = 3[tex]\sqrt{2}[/tex]/ hypotenuse
0.707 = 3[tex]\sqrt{2}[/tex]/ hypotenuse
hypotenuse = 4.24
A parallelogram with vertices H(-2, 2),
J(5,2), K(-3, 3), and L(-4, -3) is dilated
to form a parallelogram with vertices.
H'(-5,5), J'(12.5, 5), K'(-7.5, 7.5), and
L'(-10, 7.5). Which representation best
explains the effect of this dilation?
A. (x,y) -> (3x, 3y)
Original
B. (x,y) -> (2.5x, 2.5y)
C. (x,y) -> (2x, 2y)
D. (x,y) -> (1.5x, 1.5y)
Answer: B
Step-by-step explanation:
Simplify 6° = 63
O A. 126
O B. 66
O C. 6-6
O D. 63
Answer:
i think its c 6-6 so good luck
The quotient of a number and 6 minus -1/3 is equal to the quotient of the number and 8. What is the number?
Answer:
x = 8
Step-by-step explanation:
Let the number = x
x/6 - 1/3 = x/8
-1/3 = x/8 - x/6
-1/3 = (6x-8x)/48
-1/3 = -2/48x
Divide both sides by -2/48
x = -1/3 ÷ -2/48
= -1/3 × -48/2
= 48/6
= 8
x = 8
The number = 8
What is the value of x in the solution to the system of equations below?
15x - 12y = 13
30x + 9y = 4
Answer:
1/3
Step-by-step explanation:
Use the elimination method.
15x - 12y = 13
30x + 9y = 4
If you add both equations you will not cancel out any variables, so you need to multiply one of the equations by something. Multiply the first equation by -2 to cancel out the x values.
-2(15x - 12y = 13)
30x + 9y = 4
You should have these two equations now:
-30x + 24y = -26
30x + 9y = 4
Add them together now. You should get this now.
33y = -22
Divide both sides by 33. You should get y = -2/3
Now, substitute the y value into any of the two equations that you started with. Let's substitute the y value for the second equation.
30x + 9 (-2/3) = 4
30x - 6 = 4
30x = 10
30 30 (divide 30 and 10 by 30)
x = 1/3
Easy points, what’s 9+10?
Answer:
19
Step-by-step explanation:
[tex]8 \sqrt{72} [/tex]
how to solve ??
Answer:
[tex]8 \sqrt{72} = 8 \sqrt{3 \times 3 \times 2 \times 2 \times 2} \\ = 8 \times 3 \times 2 \times \sqrt{2} = 48 \sqrt{2} [/tex]
48√2 is the right answer.plz help me with math :)
Answer:
it would be 3 in the first box and 24 in the other
Step-by-step explanation:
because the ratio is 3 years to 24 montsh most of the time the larger number is on the left and the smaller number is on the right and 3 years is more than 24 months 24 months is only two years
help please i have an f!!
Answer:
1x=3y
-9x=-2y
Step-by-step explanation:
6x=-4y
17x=-2y
4y
17x=-2y
A line passes through the points (-8, 7) and (-11,-11). Find the value of a such 1 point
that the point (-7,a) lies on the line. a=
Your answer
Answer:
a=12
Step-by-step explanation:
we need the slope of this line. Find it with the slope formula
m= y2-y1 / x2-x1 with the points given p1=(-8,7) and p2=(-11,-11)
m=-11-7 / -11-(-8) (x1,y1) (x2,y2)
m= -18 /-11+8
m= -18 / - 3
m= 6
next plug in one of the point into the point-slope formula [y-y1=m(x-x1)]
y-7=6(x-(-8)) ( simplify this towards the slope intercept form [y=mx+b]
y-6=6(x+8)
y-6=6x+48
y=6x+54
now we can plug in our point of (-7,a) to find what a is
a=6(-7)+54
a=-42+54
a=12
:)
Please help me if you can
Answer:
1)-9x^5 + 7x^2 + 3 2) -2x2 • (x - 7) 3) -23v^2 + 7v + 4 4) is just 7x
Solve for x
PLS HURRY
7x-6y=9
5x+2y=19 Solve the system using elimination.
Step-by-step explanation:
multiply 5x+2y=19 by 3 youll get 15x+6y=57
eliminate y
7x-6y=9
15x+6y=57 +
22x=66
x=3
substitute x to 5x+2y=19
15+2y=19
2y=4
y=2
7x-(3x+5)-8 = (1/2)*(8x+20) -7x +5
and
5(3x+4) -2x = 7x -3(-2x+11)
Answer:
For the first problem the answer is x=4
The second Problem the answer is no solutions
Step-by-step explanation:
7x−(3x+5)−8=1/2 (8x+20)−7x+5
7x+−3x+−5+−8=1/2(8x) +(1/2) (20)+−7x+5(Distribute)
7x+−3x+−5+−8=4x+10+−7x+5
(7x+−3x)+(−5+−8)=(4x+−7x)+(10+5)(Combine Like Terms)
4x+−13=−3x+15
4x−13=−3x+15
Step 2: Add 3x to both sides.
4x−13+3x=−3x+15+3x
7x−13=15
Add 13 to both sides.
7x−13+13=15+13
7x=28 Divide both sides by 7.
x=4
5(3x+4) -2x = 7x -3(-2x+11)
Simplify both sides of the equation.
5(3x+4)−2x=7x−3(−2x+11)
(5)(3x)+(5)(4)+−2x=7x+(−3)(−2x)+(−3)(11)(Distribute)
15x+20+−2x=7x+6x+−33
(15x+−2x)+(20)=(7x+6x)+(−33)(Combine Like Terms)
13x+20=13x+−33
13x+20=13x−33
Subtract 13x from both sides.
13x+20−13x=13x−33−13x
20=−33
Step 3: Subtract 20 from both sides.
20−20=−33−20
0=−53
There are no solutions.
Answer:
Step-by-step explanation:
7x-(3x+5)-8 = (1/2)*(8x+20) -7x +5
1. Distributive Property
7x - 3x - 5 - 8 = 4x + 20 - 7x + 5
2. Combine like terms
4x -13 = -3x + 25
3. Add 13 on both sides
4x -13 + 13 = -3x + 25 + 13
4x = -3x + 38
4. Add 3x on both sides
4x + 3x = -3x + 3x + 38
7x = 38
5. Divide by 7 on both sides
7x / 7= 38 / 7
x = 5.428571428571429
or
x = 5.4
__________________________________________________________
5(3x+4) -2x = 7x -3(-2x+11)
1. Distributive Property
15x + 20 - 2x = 7x + 6x - 33
2. Combine like terms
13x + 20 = 13x - 33
3. Subtract 20 on both sides
13x + 20 - 20 = 13x - 33 - 20
13x = 13x - 53
4. Subtract 13x on both sides
13x - 13x = 13x - 13x - 53
0 = -53 ( there is no answer for x)
Hope this helped!!!!
38=p−15
PLEASE HELP MEHHHHH
Answer:
p=23
Step-by-step explanation:
Answer:
P=23
Step-by-step explanation:
38-15=23
p=23
Hope this helps
Have a great day!
ago
7
.
15
6
7
10. Which of the following could be the
perimeters of the three squares below?
A. 12 ft, 16 ft and 20 ft
B. 20 ft, 16 ft and 24 ft
C. 40 ft, 80 ft and 120 ft
D. 16 f1, 24 ft and 28 ft
Maneuvering the Middle LLC, 2017
Answer:
where are the squares?
Step-by-step explanation:
Solve the inequality:
11x+12≥45
Select one:
x 3
x≥3
x≤3
For the current reaction, 2NO2 ↔ N2O4, we have:
Kc = [tex]\frac{[N_{2} O_{4}]}{[NO_{2}]^{2} }[/tex]
Concentration of NO2 = 11.95
Concebtration of N2O4 = 6.05
Based on the current concentrations of NO2 and N2O4, what is Kc?
[tex]\displaystyle K_c \approx 0.0424[/tex]
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Equilibrium
Equilibrium Constant KConcentrations - Denoted in [Brackets]Step-by-step explanation:Step 1: Define
[RxN] 2NO₂ ⇆ N₂O₄
[Equilibrium Rate Law] [tex]\displaystyle K_c = \frac{[N_2O_4]}{[NO_2]^2}[/tex]
NO₂ = 11.95 M
N₂O₄ = 6.05 M
Step 2: Find K
Substitute [ERL]: [tex]\displaystyle K_c = \frac{[6.05]}{[11.95]^2}[/tex]Exponents: [tex]\displaystyle K_c = \frac{[6.05]}{[142.803]}[/tex]Divide: [tex]\displaystyle K_c = 0.042366[/tex]Round (Sig Figs): [tex]\displaystyle K_c \approx 0.0424[/tex]This value of K tells us that the reactants are favored in the equilibrium reaction (K < 0.1).
Roger’s father knows that Dial It Up sells data plans at $16 for 2 gigabytes and Ring Ring sells data plans at $9 for 1 gigabyte. Use this information to calculate the ratio of the number of gigabytes to the price in dollars for Dial It Up and Ring Ring.
Answer:
dial it up
2:16
simplify
1:8
now multiply 8 by the number of gigs
2:16
3:24
and so on.....
ring ring
1:9
again multiply the cost by the number of gigs
2:18
3:27
and so on....
Can someone please help me? I need to get 10 of these right and I don’t understand them
9514 1404 393
Answer:
(x, y) = (1, 1)
Step-by-step explanation:
About Algebra
All of Algebra is based on a few simple rules:
adding 0 doesn't change anythingmultiplying by 1 doesn't change anythingdoing the same thing to both sides of an equation doesn't change the values of the variablesanything can be substituted for its equalWhen we solve equations by substitution, we make use of these facts.
__
About Substitution
Generally, substitution in equation solving is done for the purpose of eliminating a variable from the equation. That usually means you want to write an expression for one variable in terms of other variables.
Finding the Expression to Substitute
In this set of equations, the variables are x and y. We can substitute for y an expression involving x, or we can substitute for x an expression involving y. These equations are written in such a way that either method works as well as the other.
Let's choose to substitute for y. This means we need an equation of the form ...
y = <some expression involving x>
The first equation makes it easy to get that. If we add y (to both sides, see rule 3 above), we get ...
5x -y +y = 4 +y
5x = 4 + y . . . . . . . . . simplified
Subtracting 4 (from both sides) gets us the form we want.
5x -4 = 4 -4 + y
5x -4 = y . . . . . . by rule 4 above, we can use (5x-4) anyplace you see y
Using the Expression to Substitute
Now, we have an expression for y that we can use in the second equation. There, y is multiplied by 4, so we need to be sure to multiply the whole expression by 4:
-x + 4(5x -4) = 3 . . . . . . substituted for y in the second equation
-x +20x -16 = 3 . . . . . use the distributive property to eliminate parentheses
19x -16 = 3 . . . . . . collect terms
This has a constant (-16) where we don't want it, so we can add 16 (to both sides) to get rid of it.
19x -16 +16 = 3 +16
19x = 19 . . . . simplify
Now, we can divide by 19 (to both sides) to get x by itself.
(19x)/19 = 19/19
x = 1 . . . . almost done; we still need to find y
Finishing Up
Using the equation for y that we used for substitution, we can find y from our value of x.
y = 5x -4 = 5×1 -4 = 5-4
y = 1
So, the solution is x = 1, y = 1, or (x, y) = (1, 1).
_____
Additional comment
In this set of equations, both variables (x and y) appear with coefficients of 1 (actually, -1). This makes it easy to solve for an expression that can be substituted for the variable. In systems of equations that you want to solve by substitution, it usually works well to start by looking for a variable with a coefficient of 1 (or -1). Use that to write the substitution expression as we did here.
__
Alternate Solution
If you use a variable with a coefficient other than 1 to write the substitution expression, you end up with fractions. That's OK if you're comfortable with arithmetic using fractions. It generally requires more care.
For example, we could solve the first equation for x:
x = (4 +y)/5
Substituting that into the second equation gives ...
-(4 +y)/5 +4y = 3
-4/5 -y/5 +4y = 3
(3 4/5)y = 3 4/5 . . . . . add 4/5 (to both sides), collect terms
Now, you get to divide by 3 4/5 to get ...
y = (3 4/5)/(3 4/5) = 1
Fortunately, in this case, we can see the numerator and denominator are identical, so the division result is 1. If it weren't you'd be faced with dividing mixed numbers--not always a student's first choice of fun math operations.
x = (4 +1)/5 = 1 . . . . finishing up