Answer:
-2x^{2}-12x-26
Step-by-step explanation:
(x+3)^2 = x^2+6x+9
-2(x^2+6x+9)-8
-2x^2-12x-18-8
-2x^2-12x-26
Did you ever find the answer?
The answer is here
let be L the length of each ramp
so the <span>the length of the entire dog walk, including both ramps is D, such that
</span>D=L + L + d, where d=12ft
L=hypotenus, and sin30° = 4.5ft x L so L= sin30° / 4.5= 1/2x 4.5=2.25ft
D=2.25ft+2.25ft +12ft=16.5ft
2x • 2x •2x= 8x^3
so 8x^3 is the volume of the cube