the length of each side is 28 cm.
the perimeter of the equilateral triangle is 48 cm. To find each side of the original triangle, you do 48/3=16cm. since the triangle dilate by 0.75, then you can just do 0.75*16=12cm. then you have to add 12 to 16 because the triangle gets bigger by 12 cm. so 16+12=28 cm.
