Question

If 15x + 12y = 90 then 5x + 4y = ?

A) 72
B) 80
C) 14
D) 10
E) 9
With steps pleaseee

Answer 1

30

Explanation:

15x+12y=90

Divide by 3

5x+4y=30

Answer 2

30

Explanation:

this is common sense

15x + 12y = 90

dividing throughout by 3, we would have

5x + 4y = 30

or

by equating

15x + 12y - 90=5x + 4y -30

15x -5x = 4y -12y -30 + 90

10x=60-8y

dividing throughout by 2

5x= 30-4y

5x+4y= 30