How do you solve #2/7q=-4#?

1 Answer
Jul 2, 2017

q = -14

Explanation:

To solve this problem, you need to isolate the variable, which in this case is #color(red)(q)#.

I like to think of it like #color(red)(q)# is very snobby, and wants to be alone by himself.

As you can see, in the Problem, q is stuck on the same side as #2/7#, and he really doesn't like that. So we need to cancel it out somehow. And to do this we will use reciprocals.

What exactly is a reciprocal? Well reciprocals are basically the exact opposite of a fraction, because they are flipped over. See, when you multiply any fraction with its reciprocal, or opposite, then they cancel out and make 1. For example, the fraction #3/4#'s reciprocal would be #4/3#, and #3/4# x #4/3# = 1. So the reciprocal of #2/7# is #7/2# and we multiply the whole equation by #7/2#.