Evaluating Algebraic Expressions Examples

Evaluate the following expression when x = 2, y = -3, and z = -1.

All we need to do is replace each variable with the assigned number.

2(2) + 3(-3) – (-1)

Now simplify that junk.

4 + (-9) + 1

Last but not least, add everything up.

-5 + 1 = -4

Find the values of the following expression for x = -2, -1, 0, 1, and 2.

This question is asking us to evaluate the expression for five different values. It's probably easiest to do this in chart form.

The answers can be expressed as ordered pairs, with the x-value first and the answer second. Here are the answers in this form:

(-2, 13), (-1, 4), (0, 1), (1, 4), and (2, 13)

Which of the following values make the equation x⁴ – 1 = 0 true?

x = -2, -1, 0, 1, 2

Just like the previous problem, it's probably useful to make a chart.

Now we can see that when we plug in both -1 and 1, the value is 0, making the equation true.