The answer is: (z - 6)(z + 15)
z² + 9z - 90 = z*z + 15z - 6z - 6*15 =
= (z*z + 15z) - (6z + 6*15) =
= z(z + 15) - 6(z + 15) =
= (z - 6)(z + 15)
Answer:
It would be 5.5
for a better understanding, look it up on google
Answer:

Step-by-step explanation:
I will upload a picture with my work.
Answer:
Step-by-step explanation:
5x + y = 9
-10x + 7y = 18
10x + 2y = 18
-10x + 7y = 18
9y = 36
y = 4
5x + 4 = 9
5x = 5
x = 1
(1,4)
answer is D