This is similare problems I have to study for my exam plus linear equations.
Multiply both sides by 35, the LCD,
5x = 7x + 25
Solve for x,
x = -25/2 <==Answer
I'm assuming you want to solve for x.
You want to get everything over a common denominator. In the case of 5 and 7, the lowest common denominator is 35.
To x/7 to have a denominator of 35, we have to multiply it by 5/5: (x/7)*(5/5) = 5x/35
Do the same with 5/7: (5/7)*(5/5) = 25/35
With x/5, to get the denominator to 35 we multiply by 7/7: (x/5)*(7/7) = 7x/35
Now we have: 5x/35 = 7x/35 + 25/35. Multiply both sides by 35 to eliminate all the denominators:
(5x/35 = 7x/35 + 25/35)*35 ==> 5x = 7x + 25
Solve for x by combining like terms. Subtract 7x from both sides: -2x = 25
Divide both sides by -2: x = -12.5