Question

The product of two integers is 72. One number is two less than five times the other.

Which of the following equations could be used to find one of the numbers?

2x^2 - 5 = 72
2x^2 - 5x = 72
5x^2 - 2x = 72
5x^2 - 2 = 72

Answer 1

other number: x
one number: 5x - 2

x (5x - 2)=72
5x^2 - 2x = 72

Answer 2

`5x^(2)-2x=72`

Explanation:

Let

y------> one integer number

x----> the other integer number

we know that

`xy=72` ----> equation A

`y=5x-2` -----> equation B

substitute equation B in equation A

`x(5x-2)=72`

`5x^(2)-2x=72`