SAT Math : How to find the perimeter of a right triangle
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Example Questions
Example Question #442 : Plane Geometry
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 #13 : Triangles
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 #43 : Geometry
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 #44 : Geometry
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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