If a triangle has a leg of 21 ft, and a hypotenuse of 35 ft, what is the measure of the other leg?

1 Answer
Mar 20, 2018

See a solution process below:

Explanation:

Note: Assumption is this is a right or #90^o# triangle.

The Pythagorean Theorem states:

For a right triangle

#a^2 + b^2 = c^2#

Where:

#a# and #b# are legs of the right triangle and #c# is the hypotenuse.

Substituting for #a# and #c# and solving for #b# gives:

#(21"ft")^2 + b^2 = (35"ft")^2#

#441"ft"^2 + b^2 = 1225"ft"^2#

#441"ft"^2 - color(red)(441"ft"^2) + b^2 = 1225"ft"^2 - color(red)(441"ft"^2)#

#0 + b^2 = 784"ft"^2#

#b^2 = 784"ft"^2#

#sqrt(b^2) = sqrt(784"ft"^2)#

#b = 28"ft"#

The measure of the other leg is 28 feet