A neg# added to a pos # is a pos #?

Question

My problem is :  13=-t+4  my answer is 9=-t  but I am not sure if my - should be on the # 9 or on the varible. 

Answer 1

Nice job solving the equation so far!

In order to solve for the variable, you have one more step to go:

-t = 9 ; which is the same as (-1)(t) = 9

You can move the negative to the other side by dividing both sides by -1.

t = -9

 

Answer 2

You can always multiply both sides by -1, which will make the variable positive and the number negative. If they want you to solve for t, you want to express t by itself, without the negative sign, so multiply both sides by -1 and t=-9.