Trapezoids - Examples, Exercises and Solutions

We use the formula (base+base) multiplied by the height and divided by 2.

Note that we are only provided with one base and it is not possible to determine the size of the other base.

Therefore, the area cannot be calculated.

To find the area of the trapezoid, we would ideally use the formula:

$A = \frac{1}{2} \times (b_1 + b_2) \times h$

where $b_1$ and $b_2$ are the lengths of the two parallel sides and $h$ is the height. However, the given information is incomplete for these purposes.

The numbers provided ($6$, $7$, $12$, and $5$) do not clearly designate which are the bases and what is the height. Without this information, the dimensions cannot be definitively identified, making it impossible to calculate the area accurately.

Thus, the problem, based on the given diagram and information, cannot be solved for the area of the trapezoid.

Therefore, the correct answer is: It cannot be calculated.

To solve this problem, we'll calculate the area of the trapezoid using the standard formula:

• Step 1: Identify the given dimensions:
• Shorter base $b_1 = 5$.
• Longer base $b_2 = 8$.
• Height $h = 3$.

Step 2: We apply the trapezoid area formula, which is:

$A = \frac{1}{2} \times (b_1 + b_2) \times h$.

Step 3: Substitute the given values into the formula:

$A = \frac{1}{2} \times (5 + 8) \times 3$.

Step 4: Perform the calculations:

$A = \frac{1}{2} \times 13 \times 3$.

$A = \frac{1}{2} \times 39$.

$A = 19.5$ or $19 \frac{1}{2}$.

The area of the trapezoid is $19 \frac{1}{2}$.

To solve this problem, we'll follow these steps:

• Identify the given measurements: the lengths of the parallel sides (bases) and the height.
• Use the trapezoid area formula to calculate the area.
• Perform the necessary arithmetic to find the numerical answer.

Now, let's work through each step:
Step 1: The given measurements are $\text{Base}_1 = 9$, $\text{Base}_2 = 12$, and the height = 5.
Step 2: The formula for the area of a trapezoid is $\text{Area} = \frac{1}{2} \times (\text{Base}_1 + \text{Base}_2) \times \text{Height}$.
Step 3: Substituting the numbers into the formula, we have:
$\text{Area} = \frac{1}{2} \times (9 + 12) \times 5$

Calculating inside the parentheses first:
$9 + 12 = 21$

Then multiply by the height:
$21 \times 5 = 105$

Finally, multiply by one-half:
$\frac{1}{2} \times 105 = 52.5$

Therefore, the area of trapezoid $ABCD$ is $52.5$ .

To solve this problem, we'll follow these steps:

• Step 1: Identify the given information
• Step 2: Apply the appropriate formula
• Step 3: Perform the necessary calculations

Now, let's work through each step:

Step 1: The problem gives us the height of the trapezoid as $6 \, \text{cm}$, base BC as $4 \, \text{cm}$ and base AD as $8 \, \text{cm}$.

Step 2: We'll use the formula for the area of a trapezoid:

$A = \frac{1}{2} \times (\text{base}_1 + \text{base}_2) \times \text{height}$

Step 3: Substituting the given values into the formula:

$A = \frac{1}{2} \times (4 + 8) \times 6$

Calculating further,

$A = \frac{1}{2} \times 12 \times 6$

$A = \frac{1}{2} \times 72$

$A = 36 \, \text{cm}^2$

Therefore, the area of the trapezoid ABCD is $36 \, \text{cm}^2$.

Formula for the area of a trapezoid:

$\frac{(base+base)}{2}\times altura$

We substitute the data into the formula and solve:

$\frac{9+12}{2}\times5=\frac{21}{2}\times5=\frac{105}{2}=52.5$

To find the perimeter we will add all the sides:

$4+5+9+6=9+9+6=18+6=24$

To find the perimeter of the trapezoid, we will sum the lengths of all its sides. The given side lengths are:

• Base 1: $7.5$
• Base 2: $1.5$
• Leg 1: $3$
• Leg 2: $4$

Using the formula for the perimeter $P$ of the trapezoid, we have:

$P = a + b + c + d$

Substituting in the given values:

$P = 7.5 + 1.5 + 3 + 4$

Performing the addition:

$P = 7.5 + 1.5 = 9$

$P = 9 + 3 = 12$

$P = 12 + 4 = 16$

Therefore, the perimeter of the trapezoid is $16$.

To solve this problem, we'll follow these steps:

• Step 1: Identify all given side lengths of the trapezoid.
• Step 2: Apply the formula for the perimeter of the trapezoid.
• Step 3: Sum up the lengths to find the perimeter.

Now, let's work through each step:
Step 1: The problem gives us the lengths of the trapezoid's sides:
- $AB = 2.5$
- $BC = 10.4$
- $CD = 5.3$
- $DA = 6$

Step 2: We use the formula for the perimeter of a trapezoid:

$P = AB + BC + CD + DA$

Step 3: Plugging in the given values, we calculate:

$P = 2.5 + 10.4 + 5.3 + 6$

Calculating further, we have:

$P = 24.2$

Therefore, the perimeter of the trapezoid is $24.2$.

In order to calculate the perimeter of the trapezoid we must add together the measurements of all of its sides:

7+10+7+12 =

36

And that's the solution!

Let's recall that in an isosceles trapezoid, the sum of the two angles on each of the trapezoid's legs equals 180 degrees.

In other words:

$A+C=180$

$B+D=180$

Since angle D is known to us, we can calculate:

$180-50=B$

$130=B$

Given that the trapezoid is isosceles and the angles on both sides are equal, it can be argued that:

$∢C=∢D$

$∢A=∢B$

We know that the sum of the angles of a quadrilateral is 360 degrees.

Therefore we can create the formula:

$∢A+∢B+∢C+∢D=360$

We replace according to the existing data:

$120+120+2x+2x=360$

 $240+4x=360$

$4x=360-240$

$4x=120$

We divide the two sections by 4:

$\frac{4x}{4}=\frac{120}{4}$

$x=30$

True: in every isosceles trapezoid the base angles are equal to each other.

To solve this problem, we'll follow these steps:

• Step 1: Define the geometric properties of a trapezoid.
• Step 2: Define the geometric properties of an isosceles trapezoid.
• Step 3: Conclude whether an isosceles trapezoid has two pairs of parallel sides based on these definitions.

Now, let's work through each step:
Step 1: A trapezoid is defined as a quadrilateral with at least one pair of parallel sides.
Step 2: An isosceles trapezoid is a special type of trapezoid where the non-parallel sides (legs) are of equal length. Its defining feature is having exactly one pair of parallel sides, which is the same characteristic as a general trapezoid.
Step 3: Since the definition of a trapezoid inherently allows for only one pair of parallel sides, an isosceles trapezoid, as a type of trapezoid, cannot have two pairs of parallel sides. A quadrilateral with two pairs of parallel sides is typically designated as a parallelogram, not a trapezoid.

Therefore, the solution to the problem is that isosceles trapezoids do not have two pairs of parallel sides. No.

To determine the area of the trapezoid, we will follow these steps:

• Step 1: Identify the provided dimensions of the trapezoid.
• Step 2: Apply the formula for the area of a trapezoid.
• Step 3: Perform the arithmetic to calculate the area.

Let's proceed through these steps:

Step 1: Identify the dimensions
The given dimensions from the diagram are:
Height $h = 3$ cm.
One base $b_1 = 4$ cm.
The other base $b_2 = 7$ cm.

Step 2: Apply the area formula
To find the area $A$ of the trapezoid, use the formula:
$A = \frac{1}{2} \times (b_1 + b_2) \times h$

Step 3: Calculation
Substituting the known values into the formula:
$A = \frac{1}{2} \times (4 + 7) \times 3$

Simplify the expression:
$A = \frac{1}{2} \times 11 \times 3$

Calculate the result:
$A = \frac{1}{2} \times 33 = \frac{33}{2} = 16.5$ cm²

The area of the trapezoid is therefore $16.5$ cm².

Given the choices, this corresponds to choice : $16.5$ cm².

Therefore, the correct solution to the problem is $16.5$ cm².