Answer:
Nina practiced the viola for 11.25 hours last week.
Step-by-step explanation:
Juan practiced the violin for 9 hours last week. For each 3 hours that he practices the violin, he practices 2.5 hours of cello. So
3h violin - 2.5h cello
9h violin - xh cello
He practiced 7.5 hours of cello, the same as Nina.
For every 3 hours Nina spends practicing the viola she practices the cello for 2 hours. So:
3h viola - 2h cello
xh viola - 7.5h cello
Nina practiced the viola for 11.25 hours last week.
Answer:
A construction worker may use trigonometry when building the roof of a house. They may have to calculate the right angle that hypotenuse must sit at so water doesn't build up on the roof and cause leaks.
(this may be more of an architect's job, as they are the ones that design the houses)
or
An air traffic controller may use trigonometry to find how long it will take an airplane to land/how far the airplane is from the ground while it is in the sky (hypotenuse), based on its height from the ground (opposite) and the distance away from the runway it is (adjacent). They can also calculate the angle of elevation of the airplane from the tower they work in.
tan(40) = (y + 1.5) / (x + 20)
y + 1.5 = (x + 20)[tan(40)]
y = (x + 20)[tan(40)] - 1.5
tan(60) = (y + 1.5) / x
y + 1.5 = (x)[tan(60)]
y = (x)[tan(60)] - 1.5
(x)[tan(60)] - 1.5 = (x + 20)[tan(40)] - 1.5
(x)[tan(60)] = (x + 20)[tan(40)]
(x)[tan(60)] = (x)[tan(40)] + (20)[tan(40)]
(x)[tan(60)] - (x)[tan(40)] = (20)[tan(40)]
(x)[tan(60) - tan(40)] = (20)[tan(40)]
x = [(20)(tan(40))] / [tan(60) - tan(40)]
x = 18.8 meters
Answer:
1 inch
Step-by-step explanation:
In degrees,
arccos(0.36) = 68.89980398 ≈ 68.9°
In radians,
arccos(0.36) = 1.202528433 ≈ 1.20