I"m guessing you mean

add 5 to both sides

square both sides
x+9=x²+18x+81
minus x+9 both sides
0=x²+17x+72
factor
what 2 numbres multiply to get 72 and add to get 17?
8 and 9
0=(x+8)(x+9)
set to zer
0=x+8
x=-8
x+9=0
x=-9
test each


1-5=-4
-4=-4
true


-5=-5
true
the solutions are x=-9 and -8
Answer:
D. 95 + 47 + 5.12 12 ÷ 4 ≠ 4 ÷ 12.
Step-by-step explanation:
(70 +30) + 72 B. 21 + (-14) + (-53) O C. 67 +1 - 18. So 12÷4≠4÷1/4 + 3/4 + 2. C. 20 + 80 + (-11)
Answer:
I'm pretty sure it's y= 1/3x + 2
Step-by-step explanation:
Answer:
225 m³ or 225 cubic meters
Step-by-step explanation:
Actually it has 5 sides, the 2 bases, the 3 lateral faces.
The formula for the volume of a triangular prism is: 
Using the given measurements, we get:

The volume of the prism is 225 m³
Step-by-step explanation:
lenght = x + 8
width = x

then
Lenght = x + 8 = 20 + 8 = 28
Width = x = 20