Assuming that x is Alice’s income:
x/12 = 1500
Answer:
0.68865278
Step-by-step explanation:
3B + 4T = 11.33
9B + 5T = 23.56
Solve by elimination:
Multiply the first equation by -3 to get -9B where the 3B is
so that it will cancel with the 9B when the equations are added.
-9B - 12T = -33.99
9B + 5T = 23.56
------------------
-7T = -10.43
T = $1.49
Substitute in
3B + 4T = 11.33
3B + 4(1.49) = 11.33
3B + 5.96 = 11.33
3B = 5.37
B = $1.79
A taco costs $1.49 and a burrito costs $1.79.
Therefore 5 burritos and 7 tacos will cost
5B + 7T = 5($1.79) + 7($1.49) = $19.38
9. You need an exact answer. So I will give you it but I'll also give you an approximation because it might help you understand it more.
Because we know the cosine fo theta, we can evaluate the inverse cosine of -2/3 first to find theta.
= 131.81° approx.
Because 131.81° is in the second quadrant its third quadrant partner is 228.19°. Which would make the sine 0.75 approximately.
But we need an exact answer I suppose so which is this disgusting mess...
. I know it looks scary but it is basically all the steps we just did but without evaluating anything.
This can be simplified using: sin(x− y) = sinxcosy−cosxsiny
To... 
answer: 
10. Okay. So because we have a point we can say that...
θ = 
sin(θ) = +sin(
)
11. arcsin(-0.37) =
= -21.72°+2kπ or 201.72°+2kπ approx. where k has to be an integer
answer: idk if you want one or more solutions so I gave you them all.
12. arccos(-√3/2) = 
Remember that "k" must be an integer.
answer: 5π/6
All the points are describing a rational number! (C)