Answer:
Pythagorean theorem 
Step-by-step explanation:

X = -5
The goal of this problem is to solve for x.
To solve x in this problem you need to find a way to get it by itself on the left side, the way to do this is divide -5x by -5.
You then also have to do the same for the right side. This gives you -5.
A possible answer for x would be 18
Answer:
B
Step-by-step explanation:
This quadratic factors.
x^2 - 15x + 56
= (x - 7)(x - 8)
x - 7 = 0
x = 7
=====
x - 8 = 0
x = 8
====
{7,8}
Answer:
x = √149 km
Step-by-step explanation:
Pythagorean theorem
x^2 = 10^2 + 7^2
x^2 = 100 + 49
x^2 = 149
x = √149