Question

An integer is one more than four times a number. If the product of the two integers is 39, then find the integers?

Answer 1

3 and 13

Explanation:

Let x be the an integer
Then the 4x+1 is the other integer

`x(4x+1)=39`
`4x^2+x-39=0`
`(4x+13)(x-3)=0`

Therefore, `x=-13/4` or `x=3`. However, since it says integer, then it can only be `x=3`

The other integer is then `4(3)+1=13`