Solve by Factoring
x2+4x-32=0

-4,8

Step-by-step explanation:

(This is more of a wordy explanation, incase you don't understand how to do the problem, instead of just giving the answer right away.)

Formula: ax2 + bx +  c

x2 + 4x - 32 = 0

Find a pair of numbers that multiply to c and add to b. In this case, which numbers multiply to -32 (c) and add to 4 (b)?

First let's figure out which two numbers multiply to 32 (8 x 4).

BUT, how do we get to -32? Easy! (-8 x 4) and (-4 x 8) both equal to -32, but we need the one that can also add to 4. (-4 + 8 = 4)

-4 x 8 = -32

-4 + 8 = 4

We now have our numbers and can start factoring.

1. Plug in -4 and 8 into the equation:

x2_-4_ + 4x _+8_- 32 = 0

2. Re-write it as so:

(x2 - 4x) + (8x - 32)

3. Factor each individually, taking out as much as you can:

Let's start with (x2 - 4x) first.

We can take 2x out of the equation which will give us: (x - 2)

Now lets do (8x - 32).

We can take 8 out of the equation which will give us: (x - 2)

We are now left with (x - 2) + (2x + 8)

You are done!

(Here's what it should look like on a piece of paper):

x2 + 4x - 32 = 0

-4 x 8 = -32

-4 + 8 = 32

(x2 - 4x) + (8x - 32)

2x (x2 - 4x) + 8 (8x - 32)

       (x - 2)           (x - 2)

Final

(x - 2) (2x + 8)

I hope this helped you understand it a bit better! :)

It's honestly very straight forward. The way I wrote it made it look so complicated lol. I was just giving a detailed explanation. Also, the school system will most likely make you use the ax2 + bx + c formula.

.mp4 files, because, video

1. 22

2. 1

3. 7

4. 18

step-by-step explanation

e2020 got it right