Find the value of a.
picture below

Use the Pythagoream theorem. Note that 20 is the longest side, and is c

a² = c² - b²

c = 20, b = 12, a = a

Plug in corresponding numbers to corresponding variables

a² = (20)² - (12)²

Simplify

a² = 400 - 144

Simplify. Combine like terms

a² = 256

Isolate the a. Root both sides

√a² = √256

a = √256

a = 16

16 is your answer for a

hope this helps

answer: y = -12x + 108

step-by-step explanation: do (y = m x+b) formula.