We'll let the weight of her bird be represented with x.
So we can derive the formula: bird(x) + fish (8x) =63 ounces
x+8x=63
9x=63
x=7
So the weight of the bird is 7 ounces, but we're trying to find the weight of the fish which is 8 times the bird so:
8(7)=56
Therefore the weight of the fish is 56 ounces