You do it because if you added before you multiplied your answer would be way out in the atmosphere. I'm not sure who invented that though...
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∙ 15y agomultiply first, and then add
You have to multiply to find area you have to add to find perimiter
you are suppose to MULTIPLY on area.
multiply
You multiply.
multiply first, and then add
You have to multiply to find area you have to add to find perimiter
you are suppose to MULTIPLY on area.
Multiply
multiply
You multiply.
multiply
Multiply for the area, add for the perimeter.
170
you can multiply 281 and 3 you can add 840 and 3
you add
Add.