Answer:
x = 13/8
Step-by-step explanation:
sqrt(8x-4) +8 = 11
Subtract 8 from each side
sqrt(8x-4) +8-8 = 11-8
sqrt(8x-4) =3
Square each side
(sqrt(8x-4))^2 =3^2
8x-4 = 9
Add 4 to each side
8x-4+4 = 9+4
8x = 13
Divide by 8
8x/8 = 13/8
x = 13/8
The area formula for a parallelogram is base*height=area. Make an equation. You know the area and the height, so plug that into the equation, and you get x*18=396. Solve for x by dividing 396 by 18 and you get 22. So, the base is 22cm.
