Answer: 36.9 degrees
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Work Shown:
I'm assuming your teacher meant to say the ramp is 7 meters long and the ramp rises up 4.2 meters. It doesn't make sense the way they phrased it initially since the ramp must be the longest part (it is the hypotenuse of the right triangle).
See diagram below.
The angle of elevation is the angle made between the ramp and the ground. It's the angle amount the ramp tilts upward.
sin(angle) = opposite/hypotenuse
sin(theta) = 4.2/7
sin(theta) = 0.6
theta = arcsin(0.6)
theta = 36.869897645844
theta = 36.9
Note: inverse sine or
is the same as arcsine. Make sure your calculator is in degree mode.