Pre-Algebra Examples

 $\begin{array}{r} b_{1} = & 3.8 \\ b_{2} = & 4.2 \\ h = & 7 \end{array}$

Step 1

The area of a trapezoid is equal to $\frac{1}{2}$ times the height times the sum of the bases $b_{1} + b_{2}$ .

$\frac{1}{2} \cdot (h e i g h t) \cdot (b_{1} + b_{2})$

Step 2

Substitute the values of the height $h = 7$ and bases ( $b_{1} = 3.8$ and $b_{2} = 4.2$ ) into the formula for the area of a trapezoid.

$\frac{1}{2} \cdot 7 \cdot (3.8 + 4.2)$

Step 3

Combine $\frac{1}{2}$ and $7$ .

$\frac{7}{2} \cdot (3.8 + 4.2)$

Step 4

Cancel the common factor of $7$ and $2$ .

Tap for more steps...

Step 4.1

Rewrite $7$ as $1 (7)$ .

$\frac{1 (7)}{2} \cdot (3.8 + 4.2)$

Step 4.2

Cancel the common factors.

Tap for more steps...

Step 4.2.1

Rewrite $2$ as $1 (2)$ .

$\frac{1 \cdot 7}{1 \cdot 2} \cdot (3.8 + 4.2)$

Step 4.2.2

Cancel the common factor.

$\frac{1 \cdot 7}{1 \cdot 2} \cdot (3.8 + 4.2)$

Step 4.2.3

Rewrite the expression.

$\frac{7}{2} \cdot (3.8 + 4.2)$

Step 5

Add $3.8$ and $4.2$ .

$\frac{7}{2} \cdot 8$

Step 6

Cancel the common factor of $2$ .

Tap for more steps...

Step 6.1

Factor $2$ out of $8$ .

$\frac{7}{2} \cdot (2 (4))$

Step 6.2

Cancel the common factor.

$\frac{7}{2} \cdot (2 \cdot 4)$

Step 6.3

Rewrite the expression.

$7 \cdot 4$

Step 7

Multiply $7$ by $4$ .

$28$