Question

Two positive integers have a product of 32. One integer is twice the other. What are the integers?

Answer 1

Let
`x,y` be the two integers. Let's say that
`x` is twice
`y`, i.e.
`x = 2y`. So, their product is

`xy=2y\cdot y = 2y^2`

If we want this product to be 32, we have

`2y^2 =32 \iff y^2 = 16 \iff y = \pm 4`

So, since
`x` is twice
`y`, we have
`x = \pm 8`

So, the possible couples are
`4,8` or
`-4,-8`