### Home > CC4 > Chapter A > Lesson A.1.3 > Problem A-30

A-30.

Write a simplified algebraic expression for each Expression Mat below. Homework Help ✎ a.

b.

c.

Remove the zero pairs.

What is an expression for the remaining tiles?

2*x* − 1

On this mat, both *x*-tiles in the (+) region can be removed, since they make a zero pair.

Next, flip the −1 unit tile in the (-) region to the (+) region, and then simplify.

Unlike in parts (a) and (b), this problem has no zero pairs.

However, here is an un-simplified expression to get you started.

*x*^{2} + (−1) + (−1) − (*y* + 1 + 1)

Can you simplify that expression?