Question

(-2/5 +1/2=???? can you help? I got 9/10

Answer 1

Here you have to find the common denominator.

The denominator of -2/5 is 5
The denominator of 1/2 is 2

If we multiply:

\[\frac{-2}{5}\frac{2}{2}\]
and
\[\frac{1}{2}\frac{5}{5}\]

THE TRICK HERE IS IN TWO PARTS
1) 2/2 and 5/5 are just fancy ways of representing the number 1.
2) One times any number does not change the number.

The benefit is that we now have:

\[\frac{-4}{10}+\frac{5}{10}=\frac{-4+5}{10}\]

So... check your answer... :)

Answer 2

is body here