Question 956610
your equation is:


y = k * x^3 / z^2


when x decreased by 35.9%, then the value of x becomes x - .359 * x which is equal to .641 * x.


when z increased by 5.8%, then the value of z becomes z + .058 * z which is equal to 1.058 * z.


the new equation becomes:


y = k * (.641 * x)^3 / (1.058 * z)^2


this becomes:


y = (k * .641^3 * x^3) / (1.058^2 * x^2)


this is the same as:


y = (.641^3 / 1.058^2) * k * (x^3 / z^2)


simplify to get:


y = (.2352896118 * k * x^3) / z^2


y changes by a factor of .2352896118.


let's do an example to see if this holds true.


let x = 9 and let z = 5


when this happens, y is equal to 87.48


you get:


87.48 = k * 9^3 / 5^2


solve for k to get k = 3.


k is the constant of variation and so never changes.


now let y = k * (.641 * x)^3 / (1.058 * z)^2


when x = 9 and when z = 5 and when k = 3, this equation becomes:


y = (3 * (.641 * 9)^3) / (1.058 * 5)^2


this becomes:


y = (3 * 5.769^3) / 5.29^2 which becomes:


y = 20.58313524


the original value of y was 87.48


the new value of y is 20.58313524


the new value of y divided by the original value of y is equal to 20.58313524 / 87.48 which is equal to .2352896118.


the new value of y is equal to .2352896118 times the original value of y.


i believe that's what you are looking for.


that's the factor that the value of y was changed by.