6a=54 so a=54/6, a=9
b-a=14, and using a found above...
b-9=14
b=23, so a=9 and b=23 so
ab=9(23)=207
The equation is a circle centered at the origin with radius 8 (sqrt(64))
Therefore, the bounded region is just a quarter circle in the first quadrant.
Riemann Sum: ∑⁸ₓ₋₋₀(y²)Δx=∑⁸ₓ₋₋₀(64-x²)Δx
Definite Integral: ∫₀⁸(y²)dx=∫₀⁸(64-x²)dx