Question 754303
What should be added to (-7/20) to get (-2/5)?
--------------
(-7/20) + what =  (-2/5)
Subtract (-7/20) from both sides
what =  (-2/5) - (-7/20)
Get a common denominator
what =  (-8/20) - (-7/20)
- times - = +
what =  (-8/20) + 7/20
Combine
what = -1/20