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Special Cases, for Right Triangles 30° 60° 90° Triangles. 60°. 30 °. 45°. 45° 45° 90° Triangles. 45°. 1. 1. 1. An equilateral triangle is also equiangular , all angles are the same . 60°. 2.
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Special Cases, for Right Triangles 30° 60° 90° Triangles 60° 30° 45° 45° 45° 90° Triangles 45°
1 1 1. Anequilateraltriangleisalsoequiangular, allangles are thesame. 60° 2 2. Let’sdrawanAltitudefromone of thevertices. Whichisalso a Median and Angle bisector. 30° 60° 2 30° 3. Thebisectedsideisdividedintotwoequalsegments and thebisectedangle has nowtwo 30° equalangles. 2 60° Congratulations! Two 30° 60° 90° triangleshavejustbeenborn Oooh …and youwatched!!!!
Let’s separate the top triangle and label the unknown side as z. 2 2 1 30° 30° 1 2 2 2 2 = z + 1 2 2 4 = z + 1 2 3 = z 2 3 = z z = 3 60° 60° 60° apply the Pythagorean Theorem to find the unknown side. 1 1 30° 30° -1 -1 z = 3 z When, the smallest side is equal to 1, the hypotenuse is 2 times as big, 1 * 2 = 2 And the other leg is times as big, 1 * = Can we generalize this result for all 30°-60°-90° right triangles?
60° 2 1 30° 3 3 2 60° 1 (.5) 30° (.5) 3 (.5) 60° (2) 2 4 2 (2) 1 Yes itworks! 30° (2) Isthis true for a trianglethatistwice as big? Isthis true for a trianglethatishalfthe original size? Yes , itstillworks. Ifweknow 1 sidelength of a 30-60-90 triangle, we can use thispatterntofindtheother 2 sides
s s 3 3 s 60° 2 30° In a 30°-60°-90° triangle, thehypotenuseistwice as long as theshorterleg, and thelongerlegis times as long as theshorterleg.
3 3 3 y = x y = 2 60° 2 s s 30° s Find the values of the variables. Round your answers to the nearest hundredth. y 2x = 14 30° 2x = 14 x 2 2 14 60° x =2 Is this 30°-60°-90°? 90°-30°=60° Then we know that:
Find the values of the variables. Round your answers to the nearest unit. 2 ( ) = y = y 90 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 = x y= 60 90 30 90 30 60 30 90 = x 90 = x ( ) 2 y =104 = x 60° 3 2 s = x s x= 30° x = 52 s 2x = y 30° y 90 . OR 60° = x x Isthis a 30°-60°-90°? 90°-60°=30° OR
Find the values of the variables. Find the exact answer. 2 ( ) = y = y 30 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 3 = x y= 10 30 30 20 20 10 10 30 = x 30 = x ( ) 2 = x 60° 3 2 s = x s x= 30° s x 2x = y 60° y . 30 30° = x Is this a 30°-60°-90°? 90°-60°=30°
1 1 1 1 Let’sdraw a diagonal forthesquare. The diagonal bisectstherightangles of thesquare. Whatkind of righttriangles are formed?
1 45° 45° 45° 1 1 1 45° 45° 45° 1 1 2 2 2 y = 1 + 1 2 y = 1 + 1 2 y = 2 2 y = 2 y = 2 y The triangles are 45°-45°-90° Let’s draw the bottom triangle and label the hypotenuse as y Let’s apply the Pythagorean Theorem to find the hypotenuse.
45-45-90 Right Triangle x x Can we generalize our findings?
2 2 In a 45°-45°-90° triangle, thehypotenuseis times as long as a leg And bothlegs are thesamesize. 45° s s 45° s
Find the values of the variables. Round your answers to the nearest tenth. 36 2 2 2 2 2 2 2 2 2 2 2 2 2 2 = x 18 18 18 36 36 36 = x 36 = x ( ) 2 y = 25.5 = x 2 45° s = x s x = y = 45° x = 25.5 s 45° 36 x . If y = x then 45° OR = x y Is this a 45°-45°-90°? 90°-45°=45° OR
Find the values of the variables. Give an exact answer. 42 2 2 2 2 2 2 2 2 2 2 2 2 2 2 = x 42 21 21 21 42 42 = x 42 = x ( ) 2 = x 2 45° s = x s x = y = 45° s 45° 42 x . If y = x then 45° = x y Is this a 45°-45°-90°? 90°-45°=45°
2 2 2 21 x 45° s s y = y= 45° s Find the values of the variables. Give the exact answer. x = 21 45° y x 45° 21 Is this a 45°-45°-90°? 90°-45°=45°