Question

Solve. −9.8+(−5.9)+u=−12.4
u=?
A: 3.3
B:-8.5
C:-28.1
D:15.7

Answer 1

The answer is A, 3.3. You first want to distribute the + symbol to the 5.9, which will make it still a negative. From then you want to combine like terms so you can add -9.8+-5.9. That should be equal to -15.7. Your equation now is looking like -15.7+u=-12.4. You want to leave the u alone so now you have to do the opposite of -15.7 which is add 15.7. What you do to one side, you do to the other. Now add 15.7 to -12.4. That should be 3.3. Now it looks like u=3.3 which is your answer.

Answer 2

the best way to solve this is to simply substitute all given answers for u.

The answer is A) 3.3