Question

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A. 2(x-3)=6
B.-3(x+1)=-6
C.3(2x-3)=-39
D.-6(x+7)+3x=-42
E.|x+2|=11
F.|2x|=8
G.|3x|=27
H.|x|=-2
I.|x-3|=9
J.|2x+5|=15

Answer 1

a)2(x-3)=6

$x - 3 = \frac{6}{2}$

x-3=3

x=3+3=6

b)-3(x+1)=-6

$x + 1 = \frac{ - 6}{ - 3} \\ \\ x + 1 = \frac{6}{3}$

x+1=2

x=2-1=1

c)3(2x-3)=-39

$2x - 3 = - \frac{39}{3}$

2x-3=-13

2x=-13+3=-10

$x = - \frac{10}{2} = - 5$

d)-6(x+7)+3x=-42

-6x-42+3x=-42

-3x-42=-42

-3x=0

x=0

e)|x+2|=11

x+2=11

-(x+2)=11

x=11-2=9

-x-2=11

-x=11+2=13

x=-13

S={9,-13}

f)|2x|=8

2x=8

-2x=8

$x = \frac{8}{2} = 4 \\ \\ x = - \frac{8}{2} = - 4$

x=±4

g)|3x|=27

3x=27

-3x=27

$x = \frac{27}{3} = 9 \\ \\ x = - \frac{27}{3} = - 9$

x=±9

i)|x-3|=9

x-3=9

-(x-3)=9

x=9+3=12

-x+3=9

3-x=9

-x=9-3=6

x=-6

S={12,-6}

j)|2x+5|=15

2x+5=15

-(2x+5)=15

2x=15-5=10

$x = \frac{10}{2} = 5$

-2x-5=15

-2x=15+5=20

$x = - \frac{20}{2} = - 10$

S={5,-10}