Z is jointly proportional to x^2 and y^2. If z=379 when x=7 and y=5, find z when x=6 and y=4

Step-by-step explanation:

When two quantities are directly proportional, an increase in one quantity results to a corresponding in the other quantity.

Given that Z is jointly proportional to x² and y², if we introduce a constant of proportionality, k, the expression becomes

z = kx²y²

If z = 379 when x = 7 and y = 5, then

379 = k * 7² * 5² = 1225

k = 379/1225

Therefore, the joint proportionality function is

z = 379x²y²/1225

when x = 6 and y = 4, then

z = 379 * 6² * 4²/1225

z = 218304/1225

z = 178.2