I WILL GIVE BRAINLIST!
Showthat (a+bi)2 = (a+b)(a−b) + 2abi

see below

Step-by-step explanation:

(a + bi)²

= a² + 2abi + b²i² (This is because (a + b)² = a² + 2ab + b²; in this case, a = a and b = bi)

= a² + 2abi + b² · (-1) (This is because i² = -1)

= a² - b² + 2abi (Simplify, rearrange)

= (a + b)(a - b) + 2abi (This is because a² - b² factors to (a + b)(a - b))

Hope this helps!

i believe it is c.y = 9x

rise over run. 9 units up over 1 unit right or 9/1