Flashcard Area of A Trapezoid (p7)

Front

What is the definition of a trapezoid?

Back

A trapezoid is a four-sided figure (quadrilateral) with at least one pair of parallel sides.

Front

What is the formula for the area of a trapezoid?

Back

The area A of a trapezoid can be calculated using the formula: A = \frac{1}{2} (b_1 + b_2) h, where b_1 and b_2 are the lengths of the two parallel sides and h is the height.

Front

If a trapezoid has bases of lengths 8 in and 4 in, and a height of 3 in, what is its area?

Back

A = \frac{1}{2} (8 + 4) \cdot 3 = \frac{1}{2} \cdot 12 \cdot 3 = 18 \text{ in}^2.

Front

What is the relationship between absolute values?

Back

For any real numbers a and b, |a| > |b| means that a is further from zero than b on the number line.

Front

Evaluate the expression: |7| + |-3|.

Back

|7| + |-3| = 7 + 3 = 10.

Front

What is the absolute value of a negative number?

Back

The absolute value of a negative number is its positive counterpart. For example, |-5| = 5.

Front

How do you find the height of a trapezoid if you know the area and the lengths of the bases?

Back

Rearrange the area formula: h = \frac{2A}{b_1 + b_2}.

Front

What is the significance of the bases in a trapezoid?

Back

The bases are the two parallel sides of the trapezoid, and their lengths are used to calculate the area.

Front

If the area of a trapezoid is 36 in² and the bases are 6 in and 12 in, what is the height?

Back

Using the area formula: h = \frac{2A}{b_1 + b_2} = \frac{2 \cdot 36}{6 + 12} = \frac{72}{18} = 4 \text{ in}.

Front

What is the difference between a trapezoid and a parallelogram?

Back

A trapezoid has at least one pair of parallel sides, while a parallelogram has two pairs of parallel sides.