Is (-5)^n can be the opposite of 5^n

Rearrange the formula c^2 = a^2 + b^2 for b

100 points, hi, i’m not sure how to get the equation from the graph and table.

1. 2. ∠b and ∠y are right angles. 3.? 4.? which two statements are missing in steps 3 and 4? ∠x ≅ ∠c △abc ~ △zyx by the sas similarity theorem. ∠b ≅ ∠y △abc ~ △zyx by the sas similarity theorem. = 2 △abc ~ △zyx by the sss similarity theorem. = 2 △abc ~ △zyx by the sss similarity theorem.