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

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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