Adding and Subtracting Fractions with the Like Denominators



To add or subtract two fractions with the same denominator we add or subtract their
numerators and divide by the denominator.  Answers should always be reduced to lowest
terms.

Examples: 
1/8 + 3/8 = [1 + 3]/8 = 4/8 = 1/2 
[7t]/[10s] - [3t]/[10s] = [7t - 3t]/10s = [4t]/[10s] = [2t]/[5s] 
[2x]/[x + 1] + 2/[x + 1] = [2x + 2]/[x + 1] = [2(x + 1)]/[x + 1] = 2 
[3x + 1]/[x + 3] - [x - 5]/[x + 3] = {[3x + 1] - [x - 5]}/[x + 3] = {3x + 1 - x + 5}/[x + 3] = {2x + 6}/[x + 3]
= [2(x + 3)]/[x + 3] = 2 Warning:  When you subtract the numerator, x - 5, of the second fraction from
the numerator, 3x + 1, of the first you must put the numerator of the second
inside a symbol of grouping to indicate the whole polynomial is to be subtracted from
the first polynomial.