Answer:
Length of base DE = 24 units
Step-by-step explanation:
Given:
In given triangle, right angle at D
SO,
Perpendicular of given triangle = 32 unit
Hypotenuse of given triangle = 40 unit
Find:
Length of base DE
Computation:
Using Pythagoras theorem
Base = √Hypotenuse² - Perpendicular²
Length of base DE = √Hypotenuse of given triangle² - Perpendicular of given triangle²
Length of base DE = √40² - 32²
Length of base DE = √1,600 - 1,024
Length of base DE = √576
Length of base DE = 24 units
Answer: sqrt(2)/2 which is choice D
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Explanation
(3pi/4) radians converts to 135 degrees after multiplying by the conversion factor (180/pi).
The angle 135 degrees is in quadrant 2. We subtract the angle 135 from 180 to find the reference angle
180-135 = 45
Then you can use a 45-45-90 triangle to determine that the ratio of opposite over hypotenuse is sqrt(2)/2
sine is positive in quadrant 2
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Alternatively, you can use a unit circle. Refer to the diagram below. In red, I've circled the angle 3pi/4 radians. The terminal point for this angle has a y coordinate of sqrt(2)/2
Recall that y = sin(theta).
