Paula's dog is 36 lbs
Use the equation 48=3x+x
Add like terms: 48=4x
Divide: 12=x (x=Carla's dog's weight)
Then Multiply x by 3 to get Paula's dog's weight and you get 36 lbs
20: 30-4 x (2+5)=2
21. 17-(8-5)= 14
22. You put (10/2)-3+1, but it isn't necessary
Explanation: to solve these equations, use PEMDAS (parentheses, exponents, multiplication, division.) these equations don't involve exponents, though, so ignore that part. If 30 is left alone, you would multiply 4x2 before doing anything else. This would mean you would have 30-8+5' which gets you to 27, an incorrect answer. However, if you put parentheses around (2+5), you add those first, meaning you would then have 30-4(2+5) = 30-4(7) = 30-28= 2.
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