Converse to the Pythagorean Theorem Ch 7.2
Jan 12, 2016
Converse to the Pythagorean Theorem
Ch 7.2
Converse to the Pythagorean Theorem
• If the square of the length of the longest side of a triangle is equal to the sum of the squares of the lengths of the 2 other sides, then the triangle is a right triangle.
Verifying that something is or is not a right triangle.1. First we determine which side would be the hypotenuse.
2. Second we plug the values into the Pythagorean theorem.
222 201525 400225625
625625
222 bac
Is it a right triangle?
222 bac
222 162124
256441576
697576
Theorem 7.3
Theorem 7.4
Classify the triangle as right, obtuse or acute.
15, 20, 25
SO ACUTE
8, 9, 10
9, 10, 15
Graphing Triangles
1. When graphing triangles first plot the 3 points.
2. Decide on your method.1. Find the slope and determine whether there are
perpendicular lines. (Only works with right triangles)
2. Find the distance of each side of the triangle, then plug it back into the Pythagorean Theorem.
Graphing Triangles
A (1, 5), B(1, 1), C(6, 1)What kind of triangle is the graphed triangle?
Graphing Triangles
A (2, 4), B(4, 1), C(7, 1)What kind of triangle is the graphed triangle?
Graphing Triangles
A (3, -2), B(1, 0), C(7, 2)What kind of triangle is the graphed triangle?Find the distance of each side of the triangle
Graphing Triangles
A (3, -2), B(1, 0), C(7, 2)
22 )02()17(BClineofD
22 )20()31( ABlineofD
22 )22()37( AClineofD
212
212 )()( yyxxd
10240436)2()6( 22
22844)2()2( 22
24321616)4()4( 22 222 cba 222 )102()24()22(
40328
Graphing trianglesA (-3, 5), B(0,-2), C(4, 1)
525916)3()4()21()04( 2222 BClineofD
58499
)52()30( 22
ABlineofD
651649
)51()34( 22
AClineofD
222 cba
655825
65585222
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