Answer:
D. 70.53
Step-by-step explanation:
To solve this problem, one must use the right angle trigonometric rations. These ratios can be used to describe the ratio between the sides and an angle in a right triangle. Please note, each side is named relative to the angle that one is looking at, thus the same side can acquire different names based on the angle one uses to describe it. The trigonometric ratios are the following:

In this case, one is asked to find the measure of (<CBA), one is given the hypotenuse (the side opposite the right angle), and the side adjacent to this angle. Therefore, one should use the cosine (cos) function to find this angle.

Substitute,

Simplify

Inverse operations,

Compute,
m<CBA = 70.53
Use substitution
2x + 3(12 - 5x) = 11
Distributive property
2x + 36 - 15x = 11
Combine like terms
-13x + 36 = 11
Subtract 36
-13x = -25
x = 25/13
y = 12 - 5(25/13)
y = 31/13
Solution: x = 25/13, y = 31/13
Answer:
7/4
Step-by-step explanation:
For every 7 that y increases, x increases by 4.
Isolate the y for both questions. Note that what you do to one side, you do to the other. Do the opposite of PEMDAS.
First question: x - 5y ≥ 3
First, subtract x from both sides
x (-x) - 5y ≥ 3 (-x)
-5y ≥ -x + 3
Divide -5 from both sides. Note that when you divide by a negative number, you flip the equation.
(-5y)/-5 ≥ (-x + 3)/-5
y ≤ (-x + 3)/-5
y ≤ x/5 - 0.6
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Do the same for the second one. Subtract x from both sides
x + y < 0
x (-x) + y < 0 (-x)
y < - x
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