Answer:
D. 15 by 10.5
Explanation:
If the original painting has dimensions of 5 by 3.5, and has a scale factor of 1, then if we are trying to find the dimensions of the same thing but with a scale factor of 3, then we need to multiply the dimensions by 3.
5*3 = 15
3.5*3 = 10.5
The new dimensions are 15 by 10.5.
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