The scale factor by which the picture has been enlarged is 3.5
It is given that the width of the picture is 5 inches and the length of the picture is 17.5 inches.
Length (l) = 7 inches
Width (b) = 5 inches
The picture is a rectangle, so the area of the picture will be the product of the length and the width, that is Area = 7 * 5 = 35 square inches.
The picture has been enlarged, let k be the scale factor that has been used to enlarge the picture.
The width has been enlarged to 17.5 inches
And the length has been enlarged to 24.5 inches
So, 5 * k = 17.5 and 7* k = 24.5
After solving these two equations, we get
k = 3.5
So, the scale factor by which the picture has been enlarged is 3.5
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