<h3>
Answer:</h3>
a. -(3√13)/13
<h3>
Step-by-step explanation:</h3>
The cosine can be found from the tangent by way of the secant.
tan(θ)² +1 = sec(θ)² = 1/cos(θ)²
Then ...
cos(θ) = ±1/√(tan(θ)² +1)
The <em>cosine is negative in the second quadrant</em>, so we will choose that sign.
cos(θ) = -1/√((-2/3)² +1) = -1/√(4/9 +1) = -1/√(13/9)
cos(θ) = -3/√13 = -(3√13)/13 . . . . . matches your selection A
Answer:
D
Step-by-step explanation:
x²-4x-12≤0
x²-6x+2x-12≤0
x(x-6)+2(x-6)≤0
(x-6)(x+2)≤0
x=6,-2
∴ value of x lies between -2 & 6
Answer:
Linear equation
Step-by-step explanation:
f(x) = 2x + 15
Linear because constant increase
For this case we have the following expression:

We must find the value of the expression when:

Substituting we have:

Finally, the value of the expression is:

ANswer:
