This document provides examples of how to evaluate algebraic expressions and formulas by substituting given values for variables and simplifying. It demonstrates substituting 1 for X in the expression X + 4 to get an answer of 5, substituting 4 for X and 2 for Y in 5XY to get an answer of 40, and substituting 10 for X in the formula Y = X + 2 to solve for Y being equal to 12.

1. Review in Action

2. Remember,
To evaluate algebraic expressions
and formulas, Substitute the given
value for the variable(s) and
simplify.
Here are some examples:

3.  Evaluate the expression X + 4 for X = 1
Solution: Substitute 1 for X
1 + 4 = 5
So, the answer is 5

4.  Evaluate the expression 5XY for X = 4 and Y = 2
Solution: Substitute 4 for X and 2 for Y
5 • 4 • 2 = 40
So, the answer is 40

5.  Find the value of Y for X = 10 in the formula
Y = X + 2
Solution: Substitute 10 for X
Y = 10 + 2
So, Y = 12

6. Very simple, right?