Given a = 3 and b = - 8 ,
= > 2b² - 4a + 4a²
= > 2( - 8 )² - 4( 3 ) + 4( 3 )²
= > 2( 64 ) - 4( 3 ) + 4( 9 )
= > 128 - 12 + 36
= > 116 + 36
= > 152
The answer would be C. to find this use the rise over run method
By using what we know about right triangles, we conclude that the height is 11ft.
<h3>
How far is the top of the escalator from the ground floor? </h3>
We can think of this as a right triangle.
Where the length of the escalator is the hypotenuse
We know that the angle of depression is 42.51°, then the top angle of our right triangle is:
90° - 42.51° = 47.49°
Now, the height of the top of the escalator would be the adjacent cathetus to said angle, then we can use the relation:
cos(a) = (adjacent cathetus)/(hypotenuse)
Replacing what we know:
cos(47.49°) = height/16ft
cos(47.49°) *16ft = height = 10.8ft
Rounding to the nearest foot, we get:
height = 11ft
If you want to learn more about right triangles:
brainly.com/question/2217700
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