SAT Math : How to find the perimeter of a right triangle
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Example Question #2 :How To Find The Perimeter Of A Right Triangle
Three points in the xy-coordinate system form a triangle.
The points are
What is the perimeter of the triangle?
Drawing points gives sides of a right triangle of 4, 5, and an unknown hypotenuse.
Using the pythagorean theorem we find that the hypotenuse is
Example Question #1 :How To Find The Perimeter Of A Right Triangle
Based on the information given above, what is the perimeter of triangle ABC?
Consult the diagram above while reading the solution. Because of what we know about supplementary angles, we can fill in the inner values of the triangle. Angles A and B can be found by the following reductions:
A + 120 = 180; A = 60
B + 150 = 180; B = 30
Since we know A + B + C = 180 and have the values of A and B, we know:
60 + 30 + C = 180; C = 90
This gives us a 30:60:90 triangle. Now, since 17.5 is across from the 30° angle, we know that the other two sides will have to be √3 and 2 times 17.5; therefore, our perimeter will be as follows:
Example Question #1 :How To Find The Perimeter Of A Right Triangle
Give the perimeter of the provided triangle.
The figure shows a right triangle. The acute angles of a right triangle have measures whose sum is
Substituting
This makes
By the 45-45-90 Triangle Theorem, legs
Also by the 45-45-90 Triangle Theorem, the length of hypotenuse
The perimeter of the triangle is
Example Question #2 :How To Find The Perimeter Of A Right Triangle
What is the perimeter of the triangle above?
The figure shows a right triangle. The acute angles of a right triangle have measures whose sum is
Substituting
This makes
Rationalize the denominator by multiplying both halves of the fraction by
By the same reasoning,
The perimeter of the triangle is
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