All Basic Geometry Resources
Example Questions
Example Question #1181 : Plane Geometry
Refer to the above diagram.
True or false:
False
True
True
The distance from the origin to is the absolute value of the -coordinate of , which is . Similarly, , , and . Also, since the axes intersect at right angles, and are both right, and, consequently, congruent.
According to the Side-Angle-Side Similarity Theorem (SASS), if two sides of a triangle are in proportion to the corresponding sides of a second triangle, and their included angles are congruent, the triangles are similar.
We can test the proportion statement
by substituting:
Test the truth of this statement by comparing their cross products:
The cross-products are equal, making the proportion statement true, so two pairs of sides are in proportion. Also, their included angles and are congruent. This sets up the conditions of SASS, so .
Example Question #11 : Right Triangles
Refer to the above figure.
True, false, or inconclusive: .
False
True
Inconclusive
True
is an altitude of , so it divides the triangle into two smaller triangles similar to each other - that is, if we match the shorter legs, the longer legs, and the hypotenuses, the similarity statement is
.
Example Question #1 : How To Find The Length Of The Side Of A Right Triangle
What is the length of the remaining side of the right triangle?
Rearrange the Pythagorean Theorem to find the missing side. The Pythagorean Theorem is:
where is the hypotenuse and and are the sides.
Example Question #2 : How To Find The Length Of The Side Of A Right Triangle
The hypotenuse of a right triangle is 26 in and one leg is 10 in. What is the sum of the two shortest sides?
We use the Pythagorean Theorem so the problem to solve becomes where = unknown leg length
So and
The sum of the two legs becomes
Example Question #3 : How To Find The Length Of The Side Of A Right Triangle
Example Question #1 : How To Find The Length Of The Side Of A Right Triangle
Find the length of the unknown side, , of the right triangle below.
We need to use the Pythagorean Theorem, which says that .
Since we need to find the length of 'a', we can just solve for 'a'.
In our case, c = 12 and b = 9.
Thus, .
Example Question #2 : How To Find The Length Of The Side Of A Right Triangle
Find the missing leg of the right triangle when one of the legs is and the hypotenuse is .
In order to find the missing side of a right triangle you must use one of two things:
1. Pythagorean Theorem
2. Trigonometry.
Since we only know what the side lengths are we must use the Pythagorean Theorem.
a=4, b=x, and c=5
So the missing side length is 3
Example Question #1 : How To Find The Length Of The Side Of A Right Triangle
Given that the hypotenuse of a right triangle is and one side is , find the other side length.
To find the length of the missing side, you can either use the pythagorean theorm or realize this is a case of a special right triangle with sides .
Thus, the other side length is .
Example Question #2 : How To Find The Length Of The Side Of A Right Triangle
Find the length of the missing side.
Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for .
Now, plug in values of and into a calculator to find the length of side . Round to decimal places.
Example Question #1 : How To Find The Length Of The Side Of A Right Triangle
Find the length of the missing side.
Recall the Pythagorean Theorem for a right triangle:
Since the missing side corresponds to side , rewrite the Pythagorean Theorem and solve for .
Now, plug in values of and into a calculator to find the length of side . Round to decimal places.