How do you solve #x-(3/8)x=5#?

1 Answer
Feb 9, 2015

The quick answer is #x = 8# which you can check by substituting it back into your equation (replacing x with 8).

Two points to remember in solving this kind of equation:
1. if you multiply both sides of an equation by the same amount you still have a valid equation.
2. fractions are harder to work with than integers.

We can get rid of the fraction by multiplying the fraction by 8, but we can't multiply just part of the equation, we have to multiply all parts on both sides.

So (using a #.# for multiplication (because I haven't figured out how to use "special symbols":
# 8 * ( x - (3/8)x) = 8 * (5)#
#8x - 3x = 40# after multiplying the individual terms
#5x = 40# after subtracting
#x = 8# after dividing both sides by 5