Page 170 - Algebra 1

Example
4
Application: Landscaping
Hint
The sum of the measures of the angles of a triangle is 180°.
Jim is building a right triangular flower bed. One of the acute angles will measure twice the other acute angle. What are the measures of the two acute angles?
2x
SOLUTION
x + 2x + 90 = 180 3x + 90 = 180
-_ 9 _ 0 = -_ 9 _ 0
3x = 90
3x = 90 __
33 x = 30
x
The measures of the angles are 30° and 60°.
Solve. Justify each step. Check the solution. a. 3x+2-x+7=16
(Ex 1)
b. 6(x - 1) = 36 (Ex 2)
c. 5x - 3(x - 4) = 22 (Ex 3)
d. Geometry Juan is building a triangular shelf. He
(Ex 4)
x
x
Sum of the angle measures Combine like terms. Subtraction Property of Equality Simplify.
Division Property of Equality Simplify.
Lesson Practice
wants one angle to be a right angle and the other two angles to have the same measure. What are the measures of the angles?
Practice
Distributed and Integrated
*1. Solveforxintheequation_3 +_1x+2=0. (26) 4 2
*2. Multiple Choice A vending machine will only accept quarters in change. What are
(25)
the independent and dependent variables that describe the amount of money in change held by the vending machine?
A Independent variable: value of 1 quarter; dependent variable: number of
quarters
B Independent variable: value of 1 quarter; dependent variable: value of the quarters
C Independent variable: value of the quarters; dependent variable: number of quarters
D Independent variable: number of quarters; dependent variable: value of the quarters
Lesson 26
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