# SOLUTION: Evalute expression: 3x-4y+9 when x=2 and y=5

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 Question 175786: Evalute expression: 3x-4y+9 when x=2 and y=5Answer by Edwin McCravy(9716)   (Show Source): You can put this solution on YOUR website!Evalute expression: 3x - 4y + 9 when x=2 and y=5 ``` 3x - 4y + 9 Take out the x and put (2) in its place Take out the y and put (5) in its place: Then you have: 3(2) - 4(5) + 9 Now we must do multiplications before additions and subtractions, so take out the 3(2) and put 6 (which is 3 times 2) in its place. Also take out the 4(5) and put 20 (which is 4 times 5) in its place. Then we have: 6 - 20 + 9 Now there is only a subtraction and an addition left to do, so we must do them in the order of left to right. We come to 6 - 20 first, so we do that and get -14. Then we replace 6 - 20 by -14. Then we have -14 + 9 Now we do that addition and end up with -5. So the answer is -5. Edwin```