Answer:
x = pi/2 + 2 pi n x = pi + 2 pi n where n is an integer
x = 5pi /3 + 2 pi n
Step-by-step explanation:
8 cos^2 x + 4 cos x-4 = 0
Divide by 4
2 cos^2 x + cos x-1 = 0
Let u = cos x
2 u^2 +u -1 =0
Factor
(2u -1) ( u+1) = 0
Using the zero product property
2u-1 =0 u+1 =0
u = 1/2 u = -1
Substitute cosx for u
cos x = 1/2 cos x = -1
Take the inverse cos on each side
cos ^-1(cos x) = cos ^-1(1/2) cos ^-1( cos x) =cos ^-1( -1)
x = pi/2 + 2 pi n x = pi + 2 pi n where n is an integer
x = 5pi /3 + 2 pi n
Answer:
Step-by-step explanation:
√p^2=
I got either p or absolute p
Answer:
There are 21 twenties and 8 fifties in the drawer.
Step-by-step explanation:
This question can be solved by a system of equations.
I am going to say that:
x is the number of twenties
y is the number of fifties.
A cash drawer contains 29 bills.
This means that x + y = 29.
The total value of the bills is $820.
This means that 20x + 50y = 820.
So
x + y = 29
20x + 50y = 820
From the first equation, x = 29 - y. So:
20x + 50y = 820
20(29 - y) + 50y = 820
580 - 20y + 50y = 820
30y = 240
y = 8
And
x = 29 - y = 29 - 8 = 21
There are 21 twenties and 8 fifties.
The answer to this would be x = 20
No no need to take out the 2
You can factor this by using the ac method
2x^2 + 3x - 5 = 0
multiplying the first and last coefficients 2 * -5 = -10
Now we want to get 2 factors of -10 which will give us +3 when added:-
+5 and -2 seem ok so we write:-
2x^2 - 2x + 5x - 5 = 0
2x(x - 1) + 5 (x - 1) =0
(2x + 5)(x - 1) = 0
Solution is x = -5/2 and x = 1
