Question 243052
Step 1: Group like terms together
-3/u-7/u = -8+2-1

Step 2: find LCF of the demoninators of the equation at the left of the equal sign. Here you will realise that U is the LCF and so factorised as

-3-7/U = -7

Step 3: Solve for U value

-10/U = -7
Mutliply both sides by U

(U)-10/U = -7(U)

The two Us at left will cancel themselves and you will have:

-10 = -7U

Divide both sides by -7:

-10/-7 = -7U/-7

At the left the negatives will cancel themselves and at the right -7 as a demoninator will cancel the numerator.

Therefore, the final answer will be:
10/7 = U or U = 1 whole number, 3 over 7 (Mixed fraction)