Question 523810
4ax+12bx-7ay-21by
but this is not an equation you solve, you can only factor it
Group it
(4ax + 12bx) - (7ay + 21by); the negative outside the bracket changes the sign inside
;
Factor out 4x and 7y
4x(a + 3b) - 7y(a + 3b)
:
factor out (a+3b)
(a + 3b)(4x - 7y)