Answer:
Pythagorean theorem 
Step-by-step explanation:

Photo? i cannot answer without a photo:)
Only one because there is one variable and the combined coefficients of x are non-zero.
(0.75(x+40)=0.70(x+20), 0.05x=14-30=-16, x=-320)
Answer:
8 and 1 third.
Step-by-step explanation:
Answer:
9 meters sorry if thats wrong
Step-by-step explanation: