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Example Questions
Example Question #11 : Coordinate Geometry
The coordinates of the endpoints of , in the standard coordinate plane, are and . What is the -coordinate of the midpoint of ?
To answer this question, we need to find the midpoint of .
To find how far the midpoint of a line is from each end, we use the following equation:
and are taken from the value of the second point and and are taken from the value of the first point. Therefore, for this data:
We can then solve:
Therefore, our midpoint is units between each endpoint's value and unit between each endpoint's value. To find out the location of the midpoint, we subtract the midpoint distance from the point. (In this case it's the point .) Therefore:
So the midpoint is located at
The question asked us what the -coordinate of this point was. Therefore, our answer is .
Example Question #11 : Coordinate Geometry
Following the line , what is the distance from the the point where to the point where ?
The first step is to find the y-coordinates for the two points we are using. To do this we plug our x-values into the equation. Where , we get , giving us the point . Where , we get , giving us the point .
We can now use the distance formula: .
Plugging in our points gives us
Example Question #11 : Coordinate Geometry
Which of the following is the slope-intercept form of ?
To answer this question, we must put the equation into slope-intercept form, meaning we must solve for . Slope-intercept form follows the format where is the slope and is the intercept.
Therefore, we must solve the equation so that is by itself. First we add to both sides so that we can start to get by itself:
Then, we must subtract from both sides:
We then must divide each side by
Therefore, the slope-intercept form of the original equation is .
Example Question #1 : Solid Geometry
If we have a regular (the triangles are equilateral) triangular prism of volume and the side length of the triangle on either face is , what is the length of the prism? Write your answer in terms of a decimal rounded to the nearest hundredth.
Not enough information to decide.
The volume of a triangular prism can be simply stated as V = A*L, where A is the area of the triangular face and L is the length. We have the volume already and we need to figure out the area of the triangle from the side length.
The area of a triangle is b*h/2, and we are given the base/side length: 3 in. We also have a formula for the height of an equilateral triangle, . Calculating the area of the triangle we get 2.5981 in^2, so now we just have to plug our numbers into the volume formula.
And that is the final answer.
Example Question #1 : Solid Geometry
Roberto has a swimming pool that is in the shape of a rectangular prism. His swimming pool is meters wide, meters long, and meters deep. He needs to fill up the pool for summer, and his hose fills at a rate of cubic meters per hour. How many hours will it take for Roberto to fill up the swimming pool?
First, find the volume of the pool. For a rectangular prism, the formula for the volume is the following:
For the swimming pool,
cubic meters
Now, because the hose only fills up cubic meters per hour, divide the total volume by to find how long it will take for the pool to fill.
It will take the pool hours to fill by hose.
Example Question #1 : Solid Geometry
Matt baked a rectangular cake for his mom's birthday. The cake was inches long, inches wide, and inches high. If he cuts the cake into pieces that are inches long, inches wide, and inches high, how many pieces of cake can he cut?
First, find the volume of the cake. For a rectangular prism,
Next, find the volume of each individual slice.
Now, divide the volume of the entire cake by the volume of the slice to get how many pieces of cake Matt can cut.
Example Question #2 : Solid Geometry
A cube has a surface area of . What is its volume?
First, find the side lengths of the cube.
Recall that the surface area of the cube is given by the following equation:
, where is the length of a side.
Plugging in the surface area given by the equation, we can then find the side length of the cube.
Now, recall that the volume of a cube is given by the following equation:
Example Question #3 : Solid Geometry
The volume of the right triangular prism is . Find the value of .
The volume of a right triangular prism is given by the following equation:
Now, for the given question, the height is .
Since the area of the base is a right triangle, we can plug in the given values to find .
Example Question #1 : How To Find The Volume Of A Polyhedron
The tent shown below is in the shape of a triangular prism. What is the volume of this tent in cubic feet?
The volume of a right triangular prism is given by the following equation:
Example Question #1 : How To Find The Volume Of A Polyhedron
The height of a box is twice its width and half its length. If the volume of the box is , what is the length of the box?
For a rectangular prism, the formula for the volume is the following:
Now, we know that the height is twice its width. We can rewrite that as:
We also know that the height is half its length. That can be written as:
Now, we can plug in the values of the length, width, and height in terms of height to find the height.
The question wants to find the length of the box. Plug in the value of the height in the earlier equation we wrote earlier to represent the relatioinship between the height and the length.
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