Answer:
a=3x+b/4-x
Explanation:
I dont know which variable you're supposed to solve for. But here's how i got the answer above:
Divide each term in a(4-x)=3x+b by 4-x
a(4-x)/4-x=3x/4-x+b/4-x
Then, cancel the common factor of 4-x, giving you
a=3x/4-x+b/4-x
Finally, combine the numerators over the common denominator,
giving you a=3x+b/4-x