Question

Help me solve for 18 and 19

Answer 1

Answers:

18. 2.5y-10.0=-0.5

move -10 to the other side

the sign changes from -10 to +10

2.5y-10+10= -0.5+10

2.5y= -0.5+10

2.5y= 9.5

divide by 2.5 for both sides

2.5y/2.5= 9.5

y= 3.8

19. 2(5-2z)=20-2(z-1)

Mutiply the first bracket by 2

(2)(5)= 10

(2)(-2z)= -4z

Mutiply the second bracket by 2

(-2)(z)= -2z

(-2)(-1)= 2

10-4z= 20-2z+2

10-4z= 20+2-2z - combine like terms

10-4z= 22-2z

move -4z to the other side

sign changes from -4z to +4z

10-4z+4z= 22-2z+4z

10= 22+2z

move 22 to the other side

10-22=22-22+2z

-12= 2z

divide both sides by 2

-12/2= 2z/2

z= -6

Answer 2

Hey!

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Question 18:

2.5y - 10 = -0.5

2.5y + (-10) + 10 = -0.5 + 10

2.5y = 9.5

2.5y/2.5 = 9.5/2.5

y = 3.8

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Question 19:

2(5 - 2z) = 20 - 2(z - 1)

10 + (-4z) = 20 + (-2z) + (-2)

10 + (-4z) - (-2z) = 20 + (-2z) + (-2) - (-2z)

10 + -2z = 20 + (-2)

10 + -2z - 10 = 20 + (-2) - 10

-2z = 12

-2z/-2 = 8/-2

z = -6

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Hope This Helps :)