How To Find The Perimeter Of A Trapezoid With A Missing Side
A trapezoid is a quadrilateral with two parallel sides. In geometry, you may be asked to find a missing side of a trapezoid, given the area and height. For example: a trapezoid has an area of 171 cm^2, a side of 10 cm and a height of 18 cm. How long is the missing side? Finding it takes some basic principles of geometry and a splash of algebra.
Step 1
Substitute the information given in the question to the formula for finding the area of a trapezoid (A=.5height (base1+base2)). 171=(.5)*18(10+base2).
Step 2
Multiply out .5 by 18: 171= 9(10+base 2).
Step 3
Use the distributive property to multiple out the equation: 171= 90+9(base 2).
Step 4
Use algebra to solve the remainder of the problem. Subtract 90 from both sides: 81=9(base2), then divide each side by 9. 9=base 2.
References
Cite This Article
MLA
Ellen, Stephanie. "How To Find The Perimeter Of A Trapezoid With A Missing Side" sciencing.com, https://www.sciencing.com/perimeter-trapezoid-missing-side-2393/. 24 April 2017.
APA
Ellen, Stephanie. (2017, April 24). How To Find The Perimeter Of A Trapezoid With A Missing Side. sciencing.com. Retrieved from https://www.sciencing.com/perimeter-trapezoid-missing-side-2393/
Chicago
Ellen, Stephanie. How To Find The Perimeter Of A Trapezoid With A Missing Side last modified March 24, 2022. https://www.sciencing.com/perimeter-trapezoid-missing-side-2393/