Exercise 3 Page 492

m=12

Practice makes perfect

To solve the equation, we have to isolate m on one side. Using the Subtraction Property of Equality, we will subtract 6 from both sides of the equation. This will eliminate the addition and isolate m.

21 + m = 33

LHS-21=RHS-21

21 + m - 21 = 33 - 21

Commutative Property of Addition

m + 21 - 21 = 33 - 21

Subtract terms

m = 12

To check that this solution is correct, let's substitute m=12 into the original equation and simplify.

21 + m = 33

m= 12

21 + 12 ? =33

Add terms

33 = 33 ✓

Since the left-hand side and right-hand side are equal, m=12 is the correct solution.

Vocabulary Check p.492

Skills Check and Problem Solving p.492

Hints