please show work

8) 3n+1 +8n2 – 8n – 7

9. given the function: f(x) =3x-7, find f(-2)

Set up a ratio with height over shadow height:

40/30 = x/15

Cross multiply:

40 x 15 = 30x

600 = 30x

Divide both sides by 30:

X = 20

The tree is 20 feet tall.

Answer:

20

Step-by-step explanation:

It tells you that a 40 foot pole casts a 30 foot then it asks you how tall is a tree if it casts a 15 foot shadow. We see that 30 is exactly 2 times 15

30 = 2 * 15

So we simply do that to 40 too.

40 / 2 = 20

So 20 is our answer.

Step-by-step explanation:

I'm going to explain this in standard slope intercept form (y=mx+b) because it is easiest for this situation. I will also include converting it to point slope form. I will also show how to do straight into point slope form if you find that more helpful.

First thing is to identify difference in x and y in both points. From point 1 to point to, the x changes -4 and the y changes +4. We can rapresent this in rise over run fraction

[tex] \frac{4}{ - 4} = - 1[/tex]

So the slope is -1 because the slope is the simplified rise over run fraction.

Our next step is to find the y-intercept. This is easy because the first point is the y-intercept, so -3 is our y-intercept.

Now we know the equation.

[tex]y = - x - 3[/tex]

All we have to do now is convert it into point-slope form. So here is point slope form: y + y1 = m(x + x1). Y1 is the y-intercept and m is the slope.

[tex]y - 3 = - 1(x + x1)[/tex]

So x1 is the x intercept, so to find this you find the x value when y is 0. You can do this by using the standard form I've done because it is easiest.

[tex]0 = - x - 3 \\ x = - 3[/tex]

So when y is 0, then x is -3. Here is the complete point slope form of the line.

[tex]y - 3 = - 1(x - 3)[/tex]

-----------------------------------------------------

To put the line directly into point slope for you need to find the slope, y-intercept, and x-intercept and place the values in accordingly. If you aren't given the y-intercept and x-intercept straight away it can be difficult for some putting it directly in point slope form. That is why I recommend putting it into standard form then point-slope form.

Answer:

y=-1x-3

Step-by-step explanation:

First, you have to find the slope using the formula I attached. Using this formula, you will subtract the second y from the first y, which is 1-(-3) for this problem. That equals 4, so that will be the numerator of the slope. Next, you have to subtract the second x from the first x, which is -4-0 for this problem. That equals -4, so that will be the denominator for this slope. the fraction now is [tex]\frac{4}{-4}[/tex], which is -1. The slope is -1. The current equation looks like this: y=-1x+b. Now we can solve for b, or the y-intercept. To do this, you have to use the x and y of one of the coordinates, it doesn't matter which one, the answer will be the same. Use the first one, for example. The x is 0 and the y is -3, so the our equation to find b is -3=-1(0)+b, which is -3=0+b, which is -3=b, or b=-3. So now we know what b is. Now we have to two components we need to write the equation, the slope (-1) and the y-intercept (-3). Now we can write the equation. y=-1x+(-3), or y=-1x-3.

Answer:

2:5

Step-by-step explanation:

Simplify

Answer:

2 and x are the factors of 2

Step-by-step explanation:

Answer:

It was approximately a 9% decrease. (If you need to round to the nearest tenth, 9.1. If you need to round to the nearest hundredth, 9.10).

Step-by-step explanation:

I am going to assume that the question means that Andrea could have earned 220 points on the assignment, but instead because the assignment was late, she was marked down 20 points. (Reduced to 20 points is kind of awkward wording).

Given that, 20 divided by 220 comes out to 0.0909 repeating.

0.09, as a percentage, is 9%. (Again, 0.0909, 9.09%, could be rounded up to 9.1%).

Hope this helps!

p=2(l+b) =2(3x-3) =6x=48=x=8

Answer: It’s 8

Step-by-step explanation:

Answer: 50

Step-by-step explanation: 9 divided by 3 plus 4 times 6 plus 8 equals 50

Answer:

35

Step-by-step explanation:

9 ÷ 3 + 4 · 6 + 8

Do 9 ÷ 3 first

3

Plug this value back into the equation

3 + 4 · 6 + 8

Do 4 · 6 next

24

Plug this value back into the equation

3 + 24 + 8

Add 3 to 24

27

Plug this value back into the equation

27 + 8

Add

35

Hope this helps :)

Please consider Brainliest :)

Answer:8.5

Step-by-step explanation:

Answer:

step one

find the difference between marked price and the selling price, which is 24-15.50=8.5

step two apply the formula which is, difference divided by marked or original price and then multiple by 100

eg (8.5÷24) × 100= 35.4

so now round off to the nearest percent that's 35%

Answer:

1

Step-by-step explanation:

Answer:

see below

Step-by-step explanation:

[tex]e(x)=\frac{1}{5}x\\\\e(5)= \frac{1}{5}*5\\\\\boxed{e(5)=1}[/tex]

Hope this helps.

9514 1404 393

Answer:

  $170

Step-by-step explanation:

If the price of a pair of Jordans is the same as the price of two shirts, the total purchase has a value equivalent to that of 3 Jordans.

  pair of Jordans = $510/3 = $170

Answer:

$170

Step-by-step explanation:

9514 1404 393

Explanation:

Here are the reasons:

Step-by-step explanation:

I think it's 48 square units

Answer:

x = -50/9    

General Formulas and Concepts:

Pre-Algebra

Step-by-step explanation:

Step 1: Define equation

3x - 8 - 12x = 42

Step 2: Solve for x

Answer:

[tex]50[/tex]

Step-by-step explanation:

Let [tex]x =[/tex] blank (for convenience)

[tex]20\%x=10[/tex]

[tex]0.2x=10[/tex] (change [tex]20\%[/tex] into its decimal form)

[tex]x = 10\div 0.2[/tex] (divide [tex]0.2[/tex] on both sides)

[tex]x=50[/tex]

∴ Blank = 50

Hope this helps :)

Answer:

1/9 cup of sugar for every 1/4 cup of flour

Step-by-step explanation:  Turn the 1/3 into 3/9 and I'm sure you can figure it out from there.

Answer:

45

Step-by-step explanation:

just had that q and sumbitted my quiziz and got it correct

Answer:

21

Step-by-step explanation:

becuase that's the answer lol

Answer:

she have feed 26 or 27

Step-by-step explanation:

I am confused it's 26 or27

Answer:

-5/3

Step-by-step explanation:

y2-y1      -5

--------- =  ---

x2-x1 .     3

Answer:

i think its -10

Step-by-step explanation:

hope im not wrong

Answer:

10 girls

Step-by-step explanation:

Answer: The  speed of the turtle can be found by dividing distance by time.

Michelle is the fastest turtle.

The fastest turtle is 6cm per minute

First turtle walks 3cm a minute

Second turtle walks 6cm a minute

Third turtle also walks 3cm a minute

its d b and d                                    

hope this help a lot  of people thank you for the points also have a good day                                                                                                        

Answer:

its -9 :)

dmdmonjdnkjdnb

Answer:

-9

Step-by-step explanation:

-14+5 = -9

In equations like this, look at the signs of the numbers and that will tell you what to do. Remember it like this:

"Same signs add and keep. Different signs subtract. Keep the sign of the higher number then you'll be exact"

Answer:

D (-3, 1)

Step-by-step explanation:

Answer:

Bruu for real and they don't make sense LOL

Step-by-step explanation:

Answer:

FACTS lmbooo

Step-by-step explanation: