Solve the equation
x2 + 4x - 7 = 0
by completing the square.
Give your answers correct to 2 decimal places.

Answers

Answer 1

Answer:

x ≈ 1.32, x ≈ - 5.32

Step-by-step explanation:

Given

x² + 4x - 7 = 0 ( add 7 to both sides )

x² + 4x = 7

To complete the square

add ( half the coefficient of the x- term )² to both sides

x² + 2(2)x + 4 = 7 + 4

(x + 2)² = 11 ( take the square root of both sides )

x + 2 = ± [tex]\sqrt11}[/tex] ( subtract 2 from both sides )

x = - 2 ± [tex]\sqrt{11}[/tex]

Thus

x = - 2 - [tex]\sqrt{11}[/tex] ≈ - 5.32 ( to 2 dec. places )

x = - 2 + [tex]\sqrt{11}[/tex] ≈ 1.32 ( to 2 dec. places )


Related Questions

WILL GIVE BRAINIEST AND 20 POINTS AND 5 STARS !! NEED HELP ASAP, PLEASE EXPLAIN STEP BY STEP.Kole works in an electronic store. He estimates that he spends 42% of his pay in his own store. Write the decimal that represents the amount of pay he spends in the electronics store.

Answers

Answer:

0.42

Step-by-step explanation:

move the decimal point 2 to the left

Which relation is a function?

Answers

Answer:

Top left

Step-by-step explanation:

A function means that each domain (x value) can only have 1 range (y value). Also, I'm not sure if you can recognize it, but that option is actually a parent function (y = x^2)

Answer: the 4 one

Step-by-step explanation:

hope this helped!

A right triangle with leg lengths of 4 and 3 units has to be positioned in the
coordinate plane to write a coordinate proof. Which set of coordinates
would make the proof easier to complete?

Answers

Answer:(0,4),(0,0),(3,0)

Step-by-step explanation:

It is easy to find lengths of horizontal and vertical segments and distances from (0,0) so always place one vertex at the origin and one or more sides on an axis.

As in this answer has y intercept, and x intercept, and (0,0)

PLEASE HELP ASAP!!
A student is working two jobs over the summer to pay for a new car. The student gets paid $25 for each lawn that
is mowed (C)and $15 for each pool that is cleaned (y). The student wants to earn $750 to pay for a down payment
on a car.
• Create a model in standard form to represent this linear relationship.
• Identify the x-intercept. Explain what this means in the context of the problem.
• Identify the y-intercept. Explain what this means in the context of the problem.
Identify two combinations that are solutions to this equation. Explain what these combinations mean in the
context of the problem.

Answers

Answer:

Step-by-step explanation:

- 25x + 15y = 750

- (30, 0) are coordinates of x-intercept. If there is no pool-cleaning job student has to do 30 lawn-mowing.  

- (0, 50) are coordinates of y-intercept. If there is no lawn-mowing job student has to do 50 pool-cleanings.

- ( 15 , 25 ) mean 15 lawn-mowing and 25 pool-cleanings

$25(15) + $15(25) = $750

$375 + $375 = $750

If f(n) = 2n + 1 and g(n) = 3n, find f(n) + g(n).

Answers

Answer:

Step-by-step explanation:

I WILL GIVE BARINLEST WHO HELP ME
3

Answers

Answer:

18

Step-by-step explanation:

3*6=18

8(4x-4)=-5x-32 pls help

Answers

x= 0, i believe im solving for x

Answer:

x= 0

Step-by-step explanation:

Brainliest
Answer: what is 123-12(324-234)
·ω·

Answers

Answer:

-957

Step-by-step explanation:

324-234=90

12*90=1080

123-1080=-957

16. A negative number x a negative number is always positive. *
true
false
nositi

Answers

Answer:

True.

Step-by-step explanation:

I don't know the explanation behind any of it, but a negative number, when multiples by another negative number, is always positive.

help me please thank you!!

Answers

Answer:

6+1.25t

Step-by-step explanation:

W(in the 1st month)=6+1.25

W(in the 2nd month)=6+1.25+1.25

W(in the 3rd month)=6+1.25+1.25+1.25

W(in the t months)=6+t(1.25)

Put the equation 2x+3y=1470 in function notation

Answers

Answer:

y = -[tex]\frac{2}{3}[/tex]x + 9

Step-by-step explanation:

The mass of the copper cube is 90 grams, the mass of the gold cube is 193 grams, and the mass of the silver cube is 105 grams. Which shows the metals in order from the lowest density to the greatest density?

Answers

Answer: copper, silver, gold

Step-by-step explanation:

Answer:

copper siver gold

Step-by-step explanation:

i had this question too

Nava buys dinner for $56 how much will she pay including 15% tip?

Answers

She will have to pay a Total of $64.40

LIVING ROOM Maude's living room is in the shape of a rectangle. Its dimensions are 21 feet by 14 feet. Find the length of the diagonal of the living room. Round your answer to the nearest tenth if necessary.

Answers

Answer:

25.2 feets

Step-by-step explanation:

Given that:

Rectangular shaped living room has the dimension:

21 feets by 14 feets

Length of diagonal :

Using Pythagoras :

A² = B² + C²

Diagonal² = 21² + 14²

Diagonal = √(441 + 196)

Diagonal = √637

Diagonal = 25.238

Diagonal = 25.2 feets ( nearest tenth)

What is the equation of the line?

Answers

Answer:

y=2x=2

Step-by-step explanation:

bc the line is to the right and going up so it makes it positive and it crosses 2 on the y axis and it goes up 2 times each time

James and Terry open a savings account that has a 2.75% annual interest rate, compounded monthly. They deposit
$50,000 into the account. How much will be in the account after 20 years?
a. $48,407.45
b. $90,600.15
c.$86,608.14
d.$80,894.18

Answers

Answer:

a. $48,407.45

b. $90,600.15

c.$86,608.14

d.$80,894.18

how do I solve 22-(-2c+4) =3(c+4) +c​

Answers

1. Distribute on both sides
22 - 2c - 4 = 3c + 12 + c
2. Simplify
18 - 2c = 4c + 12
3. Add like terms
18 = 6c + 12
6 = 6c
4. Solve for c by dividing
1 = c

About how many male math teachers will there be in 2016?
A. 32
B.52


Answers

Answer:

From the answers you provided the best answer is B.52

Step-by-step explanation:

It starts past 32 so there's no way it can ever be that value as the graph is continuously increasing.

Answer:

is it 32?

Step-by-step explanation:

sorry if im wrong

hope this helps

(2x2 - 4xy + 2y2) (3x-4)

Answers

Answer:

Work shown below!

Step-by-step explanation:

[tex](2x^{2} -4xy+2y^{2})(3x-4)=6x^{3}-8x^{2}-12x^{2}y+16xy+6xy^{2}-8y^{2}[/tex]

Why does multiplying the input of a linear function change
only the slope while multiplying the output changes both the slope and the
y-intercept?

Answers

Answer:

Step-by-step explanation:

If we have a linear function and we multiply the input of the function, we aren't really changing the values of the function, we're changing the rate at which those values are reached.

E.g. if you look at the attached picture, we have [tex]f(x) = 2x[/tex] and [tex]f_2(x) = 4x[/tex], which is just [tex]f(2x)[/tex]. The value when the red line is x = 1 is half that of the value of the blue line when x = 1.

The values of the f(2x) line are reaching the values of f(x) twice as fast, meaning it has a slope of twice as much. However, it still grows through the same intercept.

If you're interested in the calculus behind this, look up the chain rule of derivatives.

However, when you start changing the output of the function, you're changing the entire equation. It's not the same line anymore.

Answer this question please.​

Answers

Answer:

x = 11

Step-by-step explanation:

We know that vertical angles (opposite angles when two lines cross), are equal.

2x - 6 = 6x - 50

4x = 44

x = 11

Daniel bought 8 pairs of socks and a tshirt. The t-shirt cost $15.
Write an equation for the Total Cost Let x = the price of socks. How much was each pair of
socks if the Total Cost was $31? Show all calculations/work.

Answers

8x + 15 = 31

Or

16 + 15 = 31

Not entirely sure if this is what you were asking for but I hope this helps!

WHAT IS THE ANSWER TO B HOW MANY MILES PLEASE

Answers

Answer:

There is nothing attached

Step-by-step explanation:

No question given. What is the problem?

The tail of a kite is 1.5 feet plus twice the length of the kite. Together, the kite and tail are 15.5 ft long. Find the length of the tail.
Which equation represents the length of the tail if the length of the kite is k?
A. 2k - 1.5
B. k - 3.0
C. k + 3.0
D. 2k + 1.5

Answers

The tail of a kite is 1.5 feet plus twice the length of the kite. Together, the kite and tail are 15.5 ft long. Find the length of the tail.
Which equation represents the length of the tail if the length of the kite is k?
A. 2k - 1.5
B. k - 3.0
C. k + 3.0
D. 2k + 1.5

Your answer would be D
Can I please get brainliest

The  equation represents the length of the tail if the length of the kite is k should be considered as the 2k + 1.5.

Calculation of the equation:

Since

The tail of a kite is 1.5 feet plus twice the length of the kite. Together, the kite and tail are 15.5 ft long.

So here we assume the length be k

So here the equation be 2k + 1.5

Hence, the option d is correct.

learn more about length here: https://brainly.com/question/16946959

the graph below shows a quadratic function f(x) and an absolute value function g(x)

which of the following x-values are approximate solutions to the equation f(x)=g(x)? select all that apply​

Answers

Answer:

The x-values that are approximate solution of the equation [tex]f(x) = g(x)[/tex] are [tex]x_{1} \approx -3.5[/tex] and [tex]x_{2}\approx 5[/tex], respectively.

Step-by-step explanation:

From graph we infer that the x-values that represents a solution to the system of equations corresponds to those values of x in which both functions coincide. As we see, there are two x-values for [tex]f(x) = g(x)[/tex], which are described below:

[tex]x_{1} \approx -3.5[/tex] and [tex]x_{2}\approx 5[/tex]

The x-values that are approximate solution of the equation [tex]f(x) = g(x)[/tex] are [tex]x_{1} \approx -3.5[/tex] and [tex]x_{2}\approx 5[/tex], respectively.

Write the equation of the line that passes through
the given points.
(0, 1) and (2, 2)

Answers

Answer:

y = 1/2x + 1

General Formulas and Concepts:

Pre-Alg

Order of Operations: BPEMDASEquality Properties

Alg I

Slope-Intercept Form: y = mx + b

m - slope b - y-intercept

Slope Formula: [tex]m=\frac{y_2-y_1}{x_2-x_1}[/tex]

Step-by-step explanation:

Step 1: Define

y-intercept (0, 1)

Point (2, 2)

Step 2: Find slope m

Substitute:                    [tex]m=\frac{2-1}{2-0}[/tex]Subtract:                       [tex]m=\frac{1}{2}[/tex]

Step 3: Write equation

y = 1/2x + 1

WRITE 0,000003 56 IN SCIENTIFIC NOTATION ​

Answers

Answer:

3.56X10^-6

Step-by-step explanation:

In converting numbers to scientific notation, simply move the decimal point of the number until the numerical coefficient is greater than 1 but less than 10. Be sure to take note of the following:

1. The numerical coefficient.

2. Number of times we move the decimal point. It will be the exponent with the base of 10.

3. The direction we take in moving the decimal point. If the direction is to the right, take the negative sign for the exponent. If the direction is to the left, take the positive sign for the exponent.

Here, we move the decimal point of 0.00000356 to the right 6 times. So, we have now 3.56X10^-6.

x² – 9
x² - 2x - 15
Simplify

Answers

Answer:

x^2 - 9 = (x + 3)(x - 3) = (x - 0)^2 - 9.

x^2 - 2x - 15 = (x - 5)(x + 3) = (x - 1)^2 - 16.

I assume you mean factored form?

What is 30% of 60? A. 0.18 B. 1.8 C. 18 D. 180

Answers

Answer:

C ) 18 hope this helps !!!

Answer:

C. 18

Step-by-step explanation:

If you multiply 30%, or .3 by 60, you get 18.

** GIVING BRAINLIEST, A THANK YOU AND A 5 STARS***
SIMPLE QUESTION,
VIEW PIC
Which 3 Dimensional shape does Zorniah make?
Rectangular Prism
Square Pyramid
Triangular PrisM
Triangular pyramid
*view picture* Please help ​

Answers

Answer:

a triangular pyramid

Step-by-step explanation:

I just folded it in my head

Triangular pyramid-
this is because you can see that there are 4 triangles stacked on each other so that would be in conclusion a triangular pyramid also I looked on google cause I’m an idiot.
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