To make y the subject, we must move everything to one side and y on the other.

Good day and I hoped that helped!
Can u post pictures of the tally chart
The answer is 456 cubic units the formula is the one on the left
(H)ypotenuse (L)eg, right-triangle theorem.
based on the provided graph, we know the hypotenuses are equal, thus the tickmarks, so H is true, now the L part, we only need either of the pair of legs to be equal DM = NB or AM = CN, if either one is true, we're golden.