Question

The sum of x and y is 100. How do you express the product P of the two numbers as a function of x?

Answer 1

x+y=100

y=100-x

we have to express in products

so take product of x and y

i.e, xy

substituting

y=100-x

f(x) = x*(100-x)

f(x) = 100x-x^2