Area
The Area of an 2D shape would be the total size of its surface. Area is measured in square units such as square centimeters (\(\text{cm}^2\) ), square inches ( \(\text{in}^2\)), etc.
Area of Common Shapes
Let's look at how to calculate the area of the shapes below:
Triangle
The area of a triangle with height \(h\) and base \(b\) is calculated as:
\(A = \cfrac{1}{2} b h\)
Square
The area of a square with side length \(s\) is calculated as:
\(A = s^2\)
Rectangle
The area of a rectangle with side lengths \(l\) and \(w\) is calculated as:
\(A = lw\)
Circle
The area of a circle with radius \(r\) is calculated as:
\(A = \pi r^2\)
Trapezoid
The area of a trapezoid with side lengths, \(a\) and \(c\), and height \(h\) is calculated as:
\(A = \cfrac{1}{2} (a + c ) h\)
Parallelogram
The area of a parallelogram with side length \(a\), base length \(b\), and height \(h\) is calculated as:
\(A = bh\)
Since we know already know the rectangle's area and the length, we can use its Area formula to calculate its width:
\( A = lw\)
\( 28 = 7w\)
\(w = \cfrac{28}{7}\)
\(w = 4 \; [\text{m}]\)
Therefore, we can determine that the width of the rectangle is \(\boldsymbol{4 \; [\textbf{m}]}\).
First, we need to determine the circle's radius, which is half the diameter:
\(r = \cfrac{d}{2} = \cfrac{20}{2} = 10 \; [\text{in}]\)
Next, we can plug the radius into the circle's area formula to solve for its area:
\(A_{\text{Pizza}} = \pi r^2\)
\(A_{\text{Pizza}} = \pi (10)^2\)
\(A_{\text{Pizza}} = \pi (100) \)
\(A_{\text{Pizza}} = 314 \; [\text{in}^2]\)
Finally, to calculate the area of a single slice, we have to divide the whole pizza into \(16\) equal slices:
\(A_{\text{Slice}} = \cfrac{314}{16}\)
\(A_{\text{Slice}} = 19.625 \; [\text{in}^2]\)
Therefore, we can determine that the area of a slice of pizza is \(\boldsymbol{19.6 \; [\textbf{in}^2]}\). Tasty!