All High School Math Resources
Example Questions
Example Question #2 : How To Find The Area Of A Right Triangle
If , , and , what is the area of this triangle?
The formula for area of a triangble is .
Since , will be the base and will be the height.
Plug in our given values to solve:
Example Question #4 : How To Find The Area Of A Right Triangle
Find the area of the following triangle:
The formula for the area of a right triangle is:
where is the length of the base and is the length of the height.
Use the formulas for a a triangle to find the length of the base. The formula for a triangle is .
Our triangle is:
Plugging in our values, we get:
Example Question #5 : How To Find The Area Of A Right Triangle
Find the area of the following right triangle:
The formula for the area of a right triangle is:
where is the length of the base and is the length of the height.
Use the formulas for a triangle to find the length of the base and height. The formula for a triangle is
Our triangle is:
Plugging in our values, we get:
Example Question #3 : How To Find The Area Of A Right Triangle
You are given a right triangle with legs of length feet and feet. What is the area of this triangle?
square feet
square feet
square feet
square feet
square feet
square feet
Since we have a right triangle, and are given the lengths of the legs, we are by definition given the base and height. Recall that the legs of the triangle are those next to the right angle, and the hypotenuse is across from the right angle.
Recall the formula for the area of a triangle:
Since we know the base and height we plug them into the equation above:
We are given units of feet, so the area will be in terms of square feet. Then, our answer is square feet.
Example Question #3 : How To Find The Area Of A Right Triangle
The ratio for the side lengths of a right triangle is 3:4:5. If the perimeter is 48, what is the area of the triangle?
96
108
240
50
48
96
We can model the side lengths of the triangle as 3x, 4x, and 5x. We know that perimeter is 3x+4x+5x=48, which implies that x=4. This tells us that the legs of the right triangle are 3x=12 and 4x=16, therefore the area is A=1/2 bh=(1/2)(12)(16)=96.
Example Question #1 : How To Find The Area Of A Right Triangle
The length of one leg of an equilateral triangle is 6. What is the area of the triangle?
The base is equal to 6.
The height of an quilateral triangle is equal to , where is the length of the base.
Example Question #1 : Right Triangles
Acute angles x and y are inside a right triangle. If x is four less than one third of 21, what is y?
90
7
3
87
18
87
We know that the sum of all the angles must be 180 and we already know one angle is 90, leaving the sum of x and y to be 90.
Solve for x to find y.
One third of 21 is 7. Four less than 7 is 3. So if angle x is 3 then that leaves 87 for angle y.
Example Question #1 : Triangles
If a right triangle has one leg with a length of 4 and a hypotenuse with a length of 8, what is the measure of the angle between the hypotenuse and its other leg?
30
90
60
65
45
30
The first thing to notice is that this is a 30o:60o:90o triangle. If you draw a diagram, it is easier to see that the angle that is asked for corresponds to the side with a length of 4. This will be the smallest angle. The correct answer is 30.
Example Question #1 : How To Find An Angle In A Right Triangle
In the figure above, what is the positive difference, in degrees, between the measures of angle ACB and angle CBD?
20
50
40
30
10
10
In the figure above, angle ADB is a right angle. Because side AC is a straight line, angle CDB must also be a right angle.
Let’s examine triangle ADB. The sum of the measures of the three angles must be 180 degrees, and we know that angle ADB must be 90 degrees, since it is a right angle. We can now set up the following equation.
x + y + 90 = 180
Subtract 90 from both sides.
x + y = 90
Next, we will look at triangle CDB. We know that angle CDB is also 90 degrees, so we will write the following equation:
y – 10 + 2x – 20 + 90 = 180
y + 2x + 60 = 180
Subtract 60 from both sides.
y + 2x = 120
We have a system of equations consisting of x + y = 90 and y + 2x = 120. We can solve this system by solving one equation in terms of x and then substituting this value into the second equation. Let’s solve for y in the equation x + y = 90.
x + y = 90
Subtract x from both sides.
y = 90 – x
Next, we can substitute 90 – x into the equation y + 2x = 120.
(90 – x) + 2x = 120
90 + x = 120
x = 120 – 90 = 30
x = 30
Since y = 90 – x, y = 90 – 30 = 60.
The question ultimately asks us to find the positive difference between the measures of ACB and CBD. The measure of ACB = 2x – 20 = 2(30) – 20 = 40 degrees. The measure of CBD = y – 10 = 60 – 10 = 50 degrees. The positive difference between 50 degrees and 40 degrees is 10.
The answer is 10.
Example Question #1 : How To Find An Angle In A Right Triangle
If angle and angle , what is the value for angle ?
For this problem, remember that the sum of the degrees in a triangle is .
That means that .
Plug in our given values to solve:
Subtract from both sides: