Exercise 21 Page 443

y=-4

Practice makes perfect

To solve the equation, we have to isolate y on one side. Using the Subtraction Property of Equality, we can subtract 15 from both sides of the equation. This will eliminate addition on the left-hand side and isolate y.

y+15=11

LHS- 15=RHS- 15

y+15- 15=11- 15

Subtract terms

y=-4

To check that this solution is correct, let's substitute y=-4 into the original equation and simplify.

y+15=11

y= -4

-4+15? =11

Add terms

11=11 ✓

Because the left-hand side and right-hand side are equal, y=-4 is the correct solution.

Guided Practice p.440

Independent Practice p.441-442

H.O.T. Problems p.442

Standardized Test Practice p.442-444

Extra Practice p.443

Common Core Review p.444

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