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2 years ago

This composite figure is made up of three simpler shapes. What approximate area of the figure use 3.14 for Pi. A,B,Cor D?

Mathematics

2 answers:

photoshop1234 [79]2 years ago

7 0

If I’m right it should be 24.28 I did Alex

Sophie [7]2 years ago

5 0

Answer:

B. 24.28 square feet

Step-by-step explanation:

To find the area of the entire composite figure, you will want to <u>find the</u> <u>area of each shape in it and add them up</u>. Personally, I like to start with the easiest one so in this case I would start with the rectangle.

To find the area of the rectangle, you must multiple length and width (l × w or b × h). So you would multiple 4ft by 3ft in this problem. The area of the rectangle then is 12 squared feet (12 ft²).

Next, find the area of the triangle using the formula 1/2×b×h (base= b; height= h). This is because since triangles are basically just squares and rectangles cut in half, all you would do it do the extra step of multiplying it by 1/2. In this problem, after substituting, you would get 1/2(4)(3). The area of the triangle then is 6 squared feet (6 ft²).

Finally, you want to find the area of the semi-circle. To do so, you must use the formula for finding the area of a circle which is π(r)². It is important to pay attention to what is given in the problem because of including the wrong number in your calculations.

In this problem, you are given the diameter of a circle, but what you need is the radius (per the circle area formula) so all you need to do it half it.

<em>Diameter= 2r or Radius = 1/2D </em>

This gives you the fact that the radius of a circle from this problem is 2 because the diameter is 4. <em>HOWEVER</em>, you need to remember that this problem is not asking you to include the area of a circle, it is asking for a <em>semi</em>-circle. This means that you would have to half the answer you get.

There are two easy ways of doing so for this case like:

1/2 π(2)² 1/4 π (2)²

Just plug either equation into the calculator and have it solved to have the area of the semi-circle.

The last and easiest step is just <u>adding all 3 areas calculated</u> to get the approximate total area of the figure!

<h2>12+6+6.28= 24.28 squared feet (24.28 ft ²)</h2>

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3 years ago

A car travels 2.5 hours in a northerly Direction for 300 KM. what is the speed and velocity

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3 years ago

Evaluate this expression. 5^-3

sweet-ann [11.9K]

Answer:

$\Huge \boxed{\frac{1}{125}}$

Step-by-step explanation:

<h2>Order of operations</h2>

PEMDAS

Parenthesis, exponent, multiply, divide, add, and subtract from left to right.

Do exponent.

$\displaystyle \frac{1}{5^3}$

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$\large \boxed{\frac{1}{125}}$ , which is our answer.

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3 years ago

Suppose a tank contains 400 gallons of salt water. If pure water flows into the tank at the rate of 7 gallons per minute and the

Strike441 [17]

Answer:

Step-by-step explanation:

This is a differential equation problem most easily solved with an exponential decay equation of the form

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$3(\frac{y}{400})$