Respuesta :

jcherry99

Given

43 - 3d= d + 9

Solution

Add 3d to both sides of the equal sign

43 = d + 3d + 9

43 = 4d + 9             Subtract 9 from both sides

43 - 9 = 4d              Collect like terms on the left

34 = 4d                    Divide by 4 on both sides.

34/4 = 4d/4  

8 2/4 = d

d = 8 2/4 = 8 1/2 = 8.5

Check

LHS

43 - 3 * 8.5

43 - 25.5

17.5

RHS

d + 9

8.5 + 9

17.5

and the problem checks.

C is the answer

gmany

[tex]43-3d=d+9\qquad|\text{subtract 43 from both sides}\\\\-3d=d-34\qquad|\text{subtract d from both sides}\\\\-4d=-34\qquad|\text{divide both sides by (-4)}\\\\d=\dfrac{-34}{-4}\\\\d=\dfrac{34:2}{4:4}\\\\d=\dfrac{17}{2}\\\\\boxed{d=8\dfrac{1}{2}}\to\boxed{c.}[/tex]

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