The answer is A! If 1/3 is gone, there’s 2/3 left. To find how much 2/3 is, you would multiply 80 by 2/3
(1/2) * x^3 + 3.4y when X = 2 and Y = 5.
= (1/2) * (2^3) * 3.4(5)
= (1/2) * 8 * 17
= (1/2) * 136
= 136/2
= 68.
I think graph 2. Hope this helps!
A square + B square = C square
