Core Connections Algebra 1, 2013
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Core Connections Algebra 1, 2013 View details
2. Section 1.2
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Exercise 67 Page 30

Practice makes perfect
a To solve the equation for x, we have to isolate it on one side of the equation by performing inverse operations.
6-x-3=10
3-x=10
- x=7
x=- 7
We will check the solution by substituting it into the equation.
6-x-3=10
6-( - 7)-3? =10
6+7-3? =10
10=10
The solution is correct.
b Again, let's perform inverse operations until x is isolated.
100x+300=200
100x=- 100
x=- 1
We will check the solution by substituting it into the equation.
100x+300=200
100( - 1)+300 ? =200
- 100+300 ? =200
200=200
The solution is correct.
c Again, we will isolate x by performing inverse operations.
1/3x+4=x-2
1/3x+6=x
x+18=3x
18=2x
9=x
x=9
Let's check the solution by substituting it into the equation.
1/3x+4=x-2
1/3* 9+4 ? = 9-2
9/3+4 ? =9-2
3+4 ? =9-2
7=7
The solution is correct.
d Again, we will isolate x.
36-2x=- x+2
34-2x=- x
34=x
x=34
Let's now check this solution by substituting it into the equation. If it makes a true statement, then our solution is correct.
36-2x=- x+2
36-2( 34)? =- 34+2
36-68? =- 34+2
- 32=- 32
As we can see, x=34 is a correct solution.