A 45 foot long escalator rises from the first floor to the second floor of a shopping mall. The escalator makes a 30° angle with the horizontal. How high above the first floor is the second floor?
A. 26 ft B. 78 ft C. 22.5 ft D. 45 ft
|dw:1403471200229:dw| So we have an angle, and the hypotenuse, and we want the opposite side from the angle Which trig function uses opposite and hypotenuse?
huh?
Hmm what grade of math are you in?
10th grade geometry
Oh okay, then we'll use the special triangles way (sorry I was doing trigonometry before)
it's okay.
its a 30, 60, 90
So what we have is a 30-60-90 triangle the side ratios that we have with that type of triangle is |dw:1403471392024:dw| So the side opposite the 30 degree angle, is our shortest leg, The side opposite the right angle, is 2 times what that length will be Since we know that long side to be 45..we know the side opposite the 30 degree angle will be half the 45...... \[\large \frac{45}{2} = 22.5\]
Omg i was right yay!
I was just double checkiung
Haha great job :)
can u help me double check like 3 more
Lol sure :)
A ladder 15 feet long leans against a wall and forms an angle of 45º with the ground. How far from the wall is the ladder? A. 15 ft B. 7.5 ft C. square root of 2 D. 7.5 square root of 2
And what did you get :P
7.5
7.5 square root of 2...close :)
yay
Because that time, the side ratios are |dw:1403473159769:dw| So we have the side that relates to the √2 To figure out the other side...we need (what number times √2 = 15 ?? So \[\large x√2 = 15\] \[\large x = \frac{15}{\sqrt{2}}\] \[\large x = \frac{15\sqrt{2}}{2}\] \[\large x = 7.5\sqrt{2}\]
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