Download Modeling and Solving Two

LESSON
6.4
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Solving Two-Step
Equations
7.EE.4a
Solve word problems leading to
equations of the form px + q = r
and p(x + q) = r, where p, q, and r
are specific rational numbers. Solve
equations of these forms fluently.
Compare an algebraic solution to an
arithmetic solution, identifying the
sequence of the operations used in
each approach. Also 7.EE.4
ESSENTIAL QUESTION
How do you solve a two-step equation?
Modeling and Solving Two-Step
Equations
You can solve two-step equations using algebra tiles.
Math On the Spot
EXAMPL 1
EXAMPLE
7.EE.4
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Use algebra tiles to model and solve 3n + 2 = 11.
STEP 1
Model the equation.
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STEP 2
Remove 2 +1-tiles from
each side of the mat.
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STEP 3
Divide each side into
3 equal groups.
STEP 4
The solution is n = 3.
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Since there are
+1-tiles on
both sides of
the equation,
you can remove,
or subtract, 2
+1-tiles from
each side to
help isolate the
variable.
YOUR TURN
Use algebra tiles to model and solve each equation.
1. 2x + 5 = 11
2. 3n - 1 = 8
3. 2a - 3 = -5
4. -4y + 2 = -2
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Lesson 6.4
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