Page 33 - Math Course 2 (Book 1)

More Two-Step Equations

Three times a number increased by 7 equals 18.
MO. 1 - L7b
A. 3n – 7 = 18
B. n(3 + 7) = 18 Two-Step Equations:
C. 3n + 7 = 18 Solving Verbal Problems
D. 3(n + 7) = 18

Let’s Begin

Answer

REAL WORLD EXAMPLE

When seven is subtracted from the product of 2 EARNINGS
and a number, the result is 10. Ms. Parsons earns $48,400 per year. This is
$4150 more than three times as much as her
A. 2n – 7 = 10 daughter earns. How much does her daughter
B. 7 – 2n = 10 earn?
C. 2(n – 7) = 10
D. n(2 – 7) = 10 Explore
Ms. Parsons earns $4150 more than three times
as much as her daughter.

Answer Plan
Write an equation to represent the situation.
Let d = her daughter’s earnings.
48,400 = 4150 + 3d

Solve
48,400 = 4150 + 3d Write the
equation.

Translate and Solve an Equation 48,400 – 4150 = 4150 – 4150 + 3d Subtract 4150
from each side.
Six less than three times a number is 15.Find the
number. 44,250 = 3d Simplify.

A. –3 44,250 = 3d Divide each side
B. 3 3 3 by 3.
C. 7
D. 27 14,750 = d Simplify.

Answer Check
Multiply 3 times 14,750 and add 4150. The result is
48,400, which is Ms. Parson’s salary. The answer is
correct.

Ms. Parson’s daughter earns
Answer
$14,750.

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