Page 29 - Math Course 2 (Book 1)

Two-Step Equations

REAL WORLD EXAMPLE Combine Like Terms Before
Solving
MEASUREMENT
The formula F = 1.8C + 32 can be used to convert Example
Fahrenheit degrees to Celsius degrees. Solve the
equation to f nd the equivalent Celsius temperature Solve b – 3b + 8 = 18.
for 59°F.
b – 3b + 8 = 18 Write the equation.
59 = 1.8C + 32 Write the equation.
1b – 3b + 8 = 18 Identity Property; b = 1b
59 – 32 = 1.8C + 32 – 32 Subtract 32 from each Combine like terms, 1b and
side. –2b + 8 = 18
–3b.

27 = 1.8C Simplify.
–2b + 8 – 8 = 18 – 8 Subtract 8 from each side.
27 1.8c
1.8 = 1.8 Divide each side by 1.8 –2b = 10 Simplify.
15 = C Simplify. 2b 10 Divide each side by –2.
–2 = –2

The solution is 15. Therefore,
Answer 15º Celsius is equivalent to 59º Answer The solution is –5.
Fahrenheit.

Equations with Negative Your Turn!

Coef cients
Solve Two-Step Equations
Example Solve 4x + 3 = 19. Check your solution.

A. 4
Solve 5 – x = 7.
5 – x = 7 Write the equation. B. 5
1
5 – 1x = 7 Identity Property; x = 1x C. 5
2
5 + (–1x) = 7 Def nition of subtraction D. 88

–5 + 5 + (–1x) = –5 + 7 Add –5 to each side.
Answer
–1x = 2 Simplify.

–1x = 2 Divide each side by –1.
–1 –1 w
Solve –6 = –4. Check your solution.
x = –2 Check your solution. 6
A. –72
Answer The solution is –2 2
B.
3
C. 12

D. 72

Answer

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