SOLUTION: (12+x)/(7-x)=a/b Solve for x in terms of a and b. Help?

Algebra ->  Expressions-with-variables -> SOLUTION: (12+x)/(7-x)=a/b Solve for x in terms of a and b. Help?       Log On


   

Question 657828: (12+x)/(7-x)=a/b
Solve for x in terms of a and b. Help?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

%2812%2Bx%29%2F%287-x%29=a%2Fb.......cross multiply

%2812%2Bx%29%2Ab=a%287-x%29

b=a%287-x%29%2F%2812%2Bx%29
and
a%287-x%29=%2812%2Bx%29%2Ab

a=%2812%2Bx%29%2Ab%2F%287-x%29