Answer:
fave sport football?
and whats the ? XD
Step-by-step explanation:
Answer:his speed in still air is 6 miles per minute.
the speed of the wind is 1 mile per minute.
Step-by-step explanation:
Let x represent his speed in still air.
Let y represent the speed of the wind.
It takes Jack Frost 5 minutes to fly 35 miles with the wind. This means that his total speed would be x + y
Distance = speed × time
It means that
35 = 5(x + y)
35 = 5x + 5y - - - - - - - - - - -1
It takes him 7 minutes to go 35 miles against the wind. This means that his total speed would be x - y
It means that
35 = 7(x - y)
35 = 7x - 7y - - - - - - - - - - -2
Multiplying equation 1 by 7 and equation 2 by 5, it becomes
245 = 35x + 35y
175 = 35x - 35y
Adding both equations, it becomes
420 = 70x
x = 420/70 = 6
Substituting x = 6 into equation 1, it becomes
35 = 5 × 6 + 5y
35 = 30 + 5y
5y = 35 - 30 = 5
y = 5/5 = 1
Answer:
53.2
Step-by-step explanation:
(cos(x) + cos(y))^2 + (sin(x) - sin(y))^2 Remove the brackets
cos^2(x) + cos^2(y) + 2cos(x)*cos(y) + sin^2(x) - 2(sin(x)*sin(y) + sin^2(y) Combine these two in bold to make 1 because sin^2(x) + cos^2(x) = 1
1 + cos^2(y) + 2cos(x)*cos(y) - 2*sin(x)*cos(y) + sin^2(y)
These two in bold also make 1
2 + 2cos(x)*cos(y) - 2*sin(X)*sin(y) Bring out a common factor of 2
2 +2(cos(x)*cos(y) - sin(x)*sin(y) )
but cos(x+y ) = cos(x)*cos(y) - sin(x)*sin(y)
2 + 2* cos(x + y) is your final answer.
18 +6x = 48
6x= 48-18
6x=30
X= 30\6
X=5
