Area of Trapezoid Notes
A parallelogram is made up of two congruent trapezoids.
So, the area of a trapezoid is one half the product of the height (h)
and the sum of the bases b1 and b2.
The formula to find the area of a trapezoid is
𝐡(𝐛𝟏 + 𝐛𝟐)
A=
𝟐
Write an equation to determine the area of the trapezoid.
Write the formula
1.
The bases are 5 inches and 12 inches.
The height is 7 inches.
Replace h with 7, b1 with 5, and b2 12.
Add 5 and 12.
Multiply.
Simplify.
Write an equation to determine the area of the trapezoid.
2.
Write the formula
Write an equation to determine the missing dimension of the
trapezoid with an area of 120 square feet.
Write the formula
4.
Replace A with 120, replace b1
with 12, and b2 with 20.
Replace h with ____ , b1 with ____, and
b2 with _____.
18 ft
Add the bases
Add.
Multiply.
Multiply each side by 2.
Simplify.
Divide each side by 30.
Simplify.
Write an equation to determine the area of the trapezoid.
3.
Write an equation to determine the missing dimension of the
trapezoid with an area of 81
meters squared.
Simplify.
5.
7m
h=?
You can write and solve equations to determine missing
dimensions.