Download 1 LESSON 3.3 - Solving Two-Step Equations Goal: Solve two

LESSON 3.3 - Solving Two-Step Equations
Goal: Solve two-step equations.
Warm-up:
Solve the following equations. Be sure to state your solution and check!
1. t + 7 = 12
4. –8b = 96
2. n + 8 = 0
3. 6 = y – 4
5.
d
4
6.
5
P = 10
8
= 15
Example 1 - Solving a Two-Step Equation
Some equations require two inverse operations to solve.
Equations are solved in the REVERSE ORDER of order of operations!
a)
3x + 4 = 10
Original equation.
CHECK!
Undo addition or subtraction.
3x = _____
Simplify.
Undo multiplication or division.
x = _____
b)
2x - 5 = -15
Simplify.
Original equation.
Undo addition or subtraction.
2x = _____
Simplify.
Undo multiplication or division.
x = _____
Simplify.
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EXAMPLE 2 - Solving with a Variable in the Numerator
x
 11  4
5
Original equation
CHECK!
__________to each side to undo subtraction.
Simplify.
x

5
=
Multiply each side by _____to undo division.
x=
Simplify.
EXAMPLE 3- Solving with a Variable and a Coefficient in the Numerator
5x
= 10
3
CHECK!
Original equation
Multiply each side by _____ to undo division.
=
Divide each side by _____ to undo multiplication.
x=
Simplify.
EXAMPLE 4 - Solving with a Negative Coefficient
6 = 18 – 4x
Original equation: Same as _____________________
Subtract _____from each side to undo addition.
Simplify.
Divide each side by _________to undo multiplication.
=x
x =
Simplify.
Rewrite solution with variable on left side of equal sign.
CHECK!
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Now You Try It!
Solve the equation. Check your answer.
Practice
a
1) 17 = 10 +
2
2)
CHECK!
y
–1=9
3
3) –8x + 5= 29
4) 2 = 11 – t
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