Laura weighs 45 pounds more than her pet dog. When they are on the scale together, they weigh 85 pou

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Laura weighs 45 pounds more than her pet dog. When they are on the scale together, they weigh 85 pounds. How much does Laura weigh?

Let Laura weigh l and her dog weigh d. WE have:

1. l = d + 45
2. d + l = 85

Substitute equation (1) into Equation (2) for l:
d + d + 45 = 85

Solve for d in the equation d + d + 45 = 85

Step 1: Group the d terms on the left hand side:
(1 + 1)d = 2d

Step 2: Form modified equation
2d + 45 = + 85

Step 3: Group constants:
We need to group our constants 45 and 85. To do that, we subtract 45 from both sides
2d + 45 - 45 = 85 - 45

Step 4: Cancel 45 on the left side:
2d = 40

Step 5: Divide each side of the equation by 2
2d/2 = 40/2

d = 20

From equation (1), we substitute d = 20:
l = d + 45
l = 20 + 45
l = 65 pounds

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