Question

If If 4/y = y show that y= 2,-2.

Answer 1

If we have that

`(4)/(y)=y`

This is equivalent to:

`4=y^(2)`

If we solve for y, we get a square root. A square root has a positive and a negative result, so:

`y=\pm\sqrt[]{4}=\pm2`

y = 2 and y = -2