Question

How do I do 86+y=99 the picture that is attached to this is how the teacher wants us to do it but I don’t understand help please!

Answer 1

Okay, take for example:

1+2=3 is the same as 1=3-2

See how we changed the place of the 2. We can do that as long we change + to - and vica versa.

Let's see your example:

6+y=-8

We move the 6 on the other side of the expression with the opposite sign (it is a rule) and we get:

y=-8-6

y=-14

The answer to your question is

86+y=99

y=99-86

y=13