Core Connections Algebra 1, 2013
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Core Connections Algebra 1, 2013 View details
2. Section 4.2
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Exercise 37 Page 156

Practice makes perfect
a

To solve for a we will first simplify the left-hand side and right-hand side. Then, we will isolate a by performing inverse operations.

8a+a-3=6a-2a-3
9a-3=4a-3
5a-3=-3
5a=0
a=0

To check if the solution is correct, we will substitute it into the original equation and simplify. If the left-hand side and right-hand side are equal, the solution is correct.

8a+a-3=6a-2a-3
8( 0)+ 0-3? =6( 0)-2( 0)-3
0+0-3? =0-0-3
-3=-3 ✓

The solution is correct.

b

We are given the following equation with variable m.

(m+2)(m+3) = (m+2)(m-2) Note that the left-hand side and right-hand side are both products where (m+2) is a factor on both sides. By dividing by (m+2), we can cancel out this factor. (m+2)(m+3)/(m+2)=(m+2)(m-2)/(m+2) However, we have to be very careful. When we divide with something containing a variable, we automatically exclude any values of m that results in a division of 0. Therefore, we will not solve the equation this way. Let's instead multiply the parentheses in the given equation.

(m+2)(m+3)=(m+2)(m-2)
â–¼
Distribute (m+3) & (m-2)
m(m+3)+2(m+3)=(m+2)(m-2)
m^2+3m+2(m+3) = (m+2)(m-2)
m^2+3m+2m+6 = (m+2)(m-2)
m^2+3m+2m+6 = m(m-2)+2(m-2)
m^2+3m+2m+6 = m^2-2m+2(m-2)
m^2+3m+2m+6 = m^2-2m+2m-4
â–¼
Solve for m
m^2+5m+6=m^2-4
5m+6=- 4
5m=- 10
m=- 2

Let's check the solution.

(m+2)(m+3)=(m+2)(m-2)
( -2+2)( -2+3)? =( -2+2)( -2-2)
0(1)? =0(-4)
0=0 ✓

We have the correct solution.

c

Again, we will have to isolate the variable on one side of the equation.

x/2+1=6
x/2=5
x=10

Let's check if our solution is correct.

x/2+1=6
10/2+1? =6
5+1? =6
6=6 ✓

As we can see, the solution is correct.

d

As in previous parts, let's solve the equation by performing inverse operations until the variable t is by itself.

4t-2+t^2=6+t^2
4t-2=6
4t=8
t=2

Let's check the solution by substituting it into the original equation.

4t-2+t^2=6+t^2
4( 2)-2+( 2)^2? =6+( 2)^2
4(2)-2+4? =6+4
8-2+4? =6+4
10=10 ✓

The solution is correct.