Question

find the area. area of a trapezoid: \\( \frac { ( b _ { 1 } + b _ { 2 } ) } { 2 } \cdot h \\) \\( a = ? c m ^ { 2 } \\)

Explanation:

Step1: Substitute the values into the formula

Given \(b_1 = 3\), \(b_2=9\), \(h = 7\). The formula for the area of a trapezoid is \(A=\frac{(b_1 + b_2)}{2}\cdot h\). Substitute the values: \(\frac{(3 + 9)}{2}\cdot7\).

Step2: Calculate the sum of the bases

First, calculate \(b_1 + b_2\): \(3+9 = 12\). The expression becomes \(\frac{12}{2}\cdot7\).

Step3: Simplify the fraction

\(\frac{12}{2}=6\). The expression is now \(6\times7\).

Step4: Multiply

\(6\times7 = 42\).

Answer:

\(42\)