Answer: 27
Explanation:
There are multiple ways to do this, but the most efficient is to set up an equation.
Using the keywords write an equation:
Difference means subtraction. Since is asking for half of the difference, divide it by 2 and then set it equal to 10:
(a-7)/2=-10
Multiply both sides by 2
a-7=20
Add 7 to both sides
a=27
Have a nice day :)