What’s the fastest way to do test 5 #18 in the no calculator section?

Because this is a no calculator question, it is worth your while to take a second to strategize before you dive in. In this case, a couple seconds of thinking will tell you two things:

1. Those fractions will be easy to cancel out if you multiply by 2.
2. You’re only asked to solve for x, so substitute accordingly.

First, cancel out the fraction:

   

Now take the second equation, , and substitute:

   

You can grid in that fraction or its decimal equivalent: 5.25.