Question

The product of two integers is 72.one number is two less than 5 times the other

Answer 1

x*y=72

x = 5y-2

x=72/y

72/y=5y-2

72=5y^2-2y

5y^2 -2y - 72 = 0

(5y+18)(y-4)=0

y = -18/5 discard

or y = 4

4x=72

x=18

(18,4)

Answer 2

x*y=72
x = 5y-2

x=72/y
72/y=5y-2

72=5y^2-2y
5y^2 -2y - 72 = 0
(5y+18)(y-4)=0
y = -18/5 discard
or y = 4
4x=72
x=18

(18,4)