Answer:

Step-by-step explanation:
We want to simplify:

Recall the Pythagorean Identity:

So:

Substitute:

Factor. We can use the difference of two squares pattern:

Cancel. Hence:

Answer:
B. 3
Step-by-step explanation:
If you were to multiply the top equation by 3 then the x value for the first equation would be 6 and since the bottom equation's x value is -6, if you were to add them, they would cancel eachother off.
LOL hope this makes sense :) Please give brainliest!! Thanks!!
7x + 5 = 8x - 25
- 5 = -8x -5
-------------------------------
7x - 8x = - 5 - 25
-1x = - 30
----- -------
-1 -1
x = 30