All Basic Geometry Resources
Example Questions
Example Question #21 : How To Find An Angle In A Right Triangle
A right triangle has equal legs of , and a hypotenuse of . Find the area.
The equation to find the area of a triangle is:
In this problem, both the base and the height are 6in. By plugging in the numbers, we get
Example Question #1521 : Basic Geometry
A right triangle has another angle that is 47 degrees. What is the third angle?
The inside of a triangle has three angles that total 180 degrees. If one is 47 and the other is the right angle (90).
Then
.
To find the missing angle subtract the sum above from 180.
is the degree measurement for the third angle.
Example Question #26 : How To Find An Angle In A Right Triangle
If one angle of a right triangle measures , what is the measure of its adjacent angle?
First we need to know that no matter what type of triangle it is, when we add up the measures of all three angles, the total is . The definition of a right triangle states that one of the three angles measures . In this problem we know that one of the angles measures so we add that to to get a sum of . To find our missing angle measure we must subtract the sum of the other two angles from the total, giving us an equation that looks like this.
So our final answer is
Example Question #27 : How To Find An Angle In A Right Triangle
Refer to the above figure.
True or false: .
False
True
False
If , then is a 30-60-90 triangle. By the 30-60-90 Triangle Theorem, it would follow that hypotenuse would be twice as long as shorter leg - that is,
,
However, since and , then, substituting,
.
It follows that .
Example Question #22 : How To Find An Angle In A Right Triangle
If one angle of a right triangle is what is the measure of the third angle?
First we need to know that when we add up all 3 angles of a triangle, the sum will always equal (this is the case for all types of triangles). Since we know this is a right triangle, first we subtract (by definition all right triangles equal ).
We know another angle equals so we subtract it from and we get .
Our final answer is .
To check our answer we can add up the three angles to make sure we come up with a sum of .
Example Question #1522 : Basic Geometry
True or false:
False
True
True
By the 30-60-90 Triangle Theorem, the ratio of the length of the longer leg of a 30-60-90 triangle to that of the shorter leg is . In the given triangle, we see that this ratio is
,
the correct ratio. This is indeed a 30-60-90 triangle, and, being opposite the longer leg, has measure .
Example Question #1523 : Basic Geometry
A right triangle has side lengths of 5, 10, and 11.18 inches. One angle is 63.4 degrees. What is the measure of the other angle?
None of these.
Since this is a right triangle, simply add this right angle to the given angle and subtract from 180 degrees.
The side lengths are not relevant in this problem.