l=7w=10.5
The perimeter of a rectangle is equal to the sum of all sides of the rectangle.
length+length+width+width=2⋅(length)+2⋅(width)
Substitute the values of the length l=7 and width w=10.5 into the formula for the perimeter of a rectangle.
2⋅7+2⋅10.5
Multiply 2 by 7.
14+2⋅10.5
Multiply 2 by 10.5.
14+21
14+21
Add 14 and 21.
35
Find the Perimeter rectangle (7)(10.5)
