Step-by-step explanation:
3x+x=-7-5
4x=-12
x=-12/4
x=-3
Answer:
8x-24
Step-by-step explanation:
8(x-3)
8 times x= 8x
8 times-3= -24
Answer: 
<u>Step-by-step explanation:</u>
Pythagorean Theorem is: a² + b² = c² , <em>where "c" is the hypotenuse</em>
<em />

Note: 4² + (8√2)² = hypotenuse² → hypotenuse = 12

Note: 12² + opposite² = 20² → opposite = 16

Note: adjacent² + 5² = 6² → adjacent = √11

Note: adjacent² + 7² = (13√2)² → adjacent = 17