l=10w=20
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=10 and width w=20 into the formula for the perimeter of a rectangle.
2⋅10+2⋅20
Multiply 2 by 10.
20+2⋅20
Multiply 2 by 20.
20+40
20+40
Add 20 and 40.
60
Find the Perimeter rectangle (10)(20)