The area of a square is #w^2+14w+49# square inches. How do you find the length of each side of the square?

1 Answer
Apr 2, 2018

#w+7# inches

Explanation:

to find the area of a square, you square the length of one side.

this means that the side length of a square is the square root of its area.

if the area of a square is #w^2+14w+49#, then the side length will be the square root of #w^2+14w+49#.

to find this, it is a good idea to first factorise the expression #w^2+14w+49#.

to do this, you should find two numbers that add to make #14# and multiply to make #49#.

those two numbers here are the same number: #7# and #7#.

#7+7 = 14#
#7 * 7 = 49#

this means that the expression can be factorised to #(w+7)(w+7)#.

if you multiply out the brackets for #(w+7)(w+7)# using FOIL, you get #w^2+7w+7w+49#, which is #w^2+14w+49#.

since #w+7# and #w+7# are the same expression, #(w+7)(w+7)# can be written as #(w+7)^2#.

therefore #(w+7)^2 = w^2+14w+49#, which means that the square root of #w^2+14w+49# is #w+7#.

if the area of the square is #w^2+14w+49# square inches, then the side length is #w+7# inches.