𝐼𝑓 𝑧 𝑣𝑎𝑟𝑖𝑒𝑠 𝑗𝑜𝑖𝑛𝑡𝑙𝑦 𝑡𝑜 𝑥 𝑎𝑛𝑑 𝑡ℎ𝑒 𝑠𝑞𝑢𝑎𝑟𝑒 𝑜𝑓 𝑦, 𝑎𝑛𝑑 𝑧 = 96 𝑤ℎ𝑒𝑛 𝑥 = 3 𝑎𝑛𝑑 𝑦 = 4.

Question

𝐹𝑖𝑛𝑑 𝑧 𝑤ℎ𝑒𝑛 𝑥 = 5 𝑎𝑛𝑑 𝑦 = 7.

Answer 1

z = kxy^2
so you want z such that
z/(5*7^2) = 96/(3*4^2)
z = 490