All HiSET: Math Resources
Example Questions
Example Question #1 : Tangent
Refer to the triangle in the above diagram. Which of the following expressions correctly gives its area?
None of the other choices gives the correct response.
The area of a right triangle is half the product of the lengths of its legs, which here are and - that is,
We are given that . is the leg opposite the angle and is its adjacent leg, we can find using the tangent ratio:
Setting and , we get
Solve for by first, finding the reciprocal of both sides:
Now, multiply both sides by 8:
Now, set and in the area formula:
,
the correct choice.
Example Question #1 : Problems Involving Right Triangle Trigonometry
Evaluate in terms of .
Suppose we allow be the lengths of the opposite leg and adjacent leg and the hypotenuse, respectively, of the right triangle with an acute angle measuring . The cosine is defined to be the ratio of the length of the adjacent side to that of the hypotenuse, so
We can set the lengths of the adjacent leg and the hypotenuse to and 3, respectively. By the Pythagorean Theorem, the length of the opposite leg is
The tangent of the angle is the ratio of the length of the opposite leg to that of the adjacent leg, so
.
Example Question #4 : Problems Involving Right Triangle Trigonometry
The sine of an angle is defined to be the ratio of the length of the opposite leg of a right triangle to the length of its hypotenuse. Therefore, we can set . By the Pythagorean Theorem:
the adjacent leg of the triangle has measure
The tangent of the angle is the ratio of the length of the opposite leg to that of the adjacent leg, which is
,
the correct response.
Example Question #101 : Measurement And Geometry
What is the volume of a cylinder with a diameter of cm and a height of cm?
Step 1: Find the diameter.
If we are given the diameter, the length of the radius is one-half the diameter.
So, the radius is
Step 2: Recall the volume formula...
Volume formula of cylinder is .
Example Question #1 : Pyramids
What is the area of the base of the pyramid with volume and height ?
The formula for the volume of a pyramid is
The height of the pyramid is , so
.
The volume of the pyramid is .
Thus,
so
.
Note, the area of the base of the pyramid is
.
Thus,
.
Hence,
Example Question #1 : Use Volume Formulas To Solve Problems
A pyramid with a square base is inscribed inside a right cone with radius 24 and height 10.
Give the volume of the pyramid.
None of the other choices gives the correct response.
The volume of a pyramid with height and a base of area can be determined using the formula
.
The height of the inscribed pyramid is equal to that of the cone, so we can set . The base of the pyramid is a square inscribed inside a circle, so the length of each diagonal of the square is equal to the diameter of the circle. See the figure below, which shows the bases of the pyramid and the cone.
The circle has radius 24, so its diameter - and the lengths of the diagonals - is twice this, or 48.
The area of a square - which is also a rhombus - is equal to half the product of the lengths of its diagonals, so
Substituting for and , we get
.
Example Question #1 : Use Volume Formulas To Solve Problems
The base of a right pyramid with height 6 is a regular hexagon with sides of length 6.
Give its volume.
The regular hexagonal base can be divided by its diameters into six equilateral triangles, as seen below:
Each of the triangles has as its sidelength that of the hexagon. If we let this common sidelength be , each of the triangles has area
;
the total area of the base is six times this.
Substituting 6 for , the area of each triangle is
The total area of the base is six times this, or
The volume of a pyramid with height and a base of area can be determined using the formula
.
Set and ;
Example Question #2 : Use Volume Formulas To Solve Problems
A right pyramid and a right rectangular prism both have square bases. The base of the pyramid has sides that are 20% longer than those of the bases of the prism; the height of the pyramid is 20% greater than that of the prism.
Which of the following is closest to being correct?
The volume of the pyramid is 61.6% less than that of the prism.
The volume of the pyramid is 42.4% less than that of the prism.
The volume of the pyramid is 82.9% less than that of the prism.
The volume of the pyramid is 74.4% less than that of the prism.
The volume of the pyramid is 33.3% less than that of the prism.
The volume of the pyramid is 42.4% less than that of the prism.
The volume of a right prism with height and bases of area can be determined using the formula
.
Since its base is a square, if we let be the length of one side, then , and
The volume of a right pyramid with height and a base of area can be determined using the formula
.
Since its base is also a square, if we let be the length of one side, then , and
.
The height of the pyramid is 20% greater than the height of the prism - this is 120% of , so . Similarly, the length of a side of the base of the pyramid is 20% greater than that of a base of the prism, so . Substitute in the pyramid volume formula:
We can substitute , the volume of the prism, for . This yields
The volume of the pyramid is equal to 57.6 % of that of the prism, or, equivalently, less.
Example Question #161 : Hi Set: High School Equivalency Test: Math
A triangular pyramid in coordinate space has its vertices at the origin, , , and . In terms of , give its volume.
The pyramid in question can be seen in the diagram below:
This pyramid can be seen as having as its base the triangle on the -plane with vertices at the origin, , and ; this is a right triangle with two legs of length , so its area is half their product, or .
The altitude (perpendicular to the base) is the segment from the origin to , which has length (the height of the pyramid) .
Setting and in the formula for the volume of a pyramid:
, the correct response.
Example Question #111 : Measurement And Geometry
About the -axis, rotate the triangle with its vertices at , , and the origin. What is the volume of the solid of revolution formed?
None of the other choices gives the correct response.
When this triangle is rotated about the -axis, the resulting solid of revolution is a cone whose base has radius , and which has height . Substitute these values into the formula for the volume of a cone:
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