How do you evaluate #\frac { 2} { 7} + ( - \frac { 1} { 2} )#?

2 Answers
Jul 2, 2018

#= - 3/14#

Explanation:

#\frac { 2} { 7} + ( - \frac { 1} { 2} )#

Remove the bracket:

#= \frac { 2} { 7} - \frac { 1} { 2} #

Create a common denominator:

#= \frac { 2} { 7} * underbrace(2/2)_(=1) - \frac { 1} { 2} * underbrace(7/7)_(= 1)#

#=4/14 - 7 /14 #

#= - 3/14#

Jul 2, 2018

#-3/14#

Explanation:

When we add or subtract fractions, we need a common denominator. Let's get our denominator to be #14#.

We can do this by multiplying #2/7# by #2/2#, and #-1/2# by #7/7#. Notice, we're multiplying by #1#, so we didn't change the value of this expression.

We now have

#4/14-7/14=-3/14#

Hope this helps!