2cos^2 x = 1 + cos 2x
cos^2 x = 1/2(1 + cos 2x)
f(x) = 6cos^2 x - 4 sin 2x = 6(1/2(1 + cos 2x) - 4 sin 2x = 3 + 3cos 2x - 4sin 2x
Let's call the two numbers x and y. We can write a system of equations to describe the situation:
5x = 8y
x - y = 150
Let's solve the first equation for x:
x = 8y/5
Now we can use substitution to solve the system by plugging 8y/5 in for x in the second equation:
(8y/5) - y = 150
Simplify:
3y/5 = 150
3y = 750
y = 250
If y = 250, then x is:
x = 8(250)/5 = 400
The answer is 250 and 400.
The answer to #5 is 171
The answer to #6 is -344
Speed times time=distance
distance=6.8
speed=2.72
time=?
2.72 times ?=6.8
divide both sides by 2.72
?=2.5
answer si 2.5 hours
Answer:
137.5 Miles
Step-by-step explanation:
2 = 50 Right? So if you were to divide 50 by 2, you would get 1 = 25. All you would have to do from there would be to multiply 25 times 5.5 to get 137.5.
