Answer:
10
Step-by-step explanation:
Answer:
7x^2 + 14x - 12
Step-by-step explanation:
Add like terms:
(4x + 8x - 5) + (3x2 + 6x - 7) becomes:
4x^2 + 8x - 5 or (grouping like terms in columns):
+ 3x^2 + 6x - 7
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7x^2 + 14x - 12
The answer for this is n(3+2)
6x - 10(x + 12) = -4x - 24
<em><u>Distributive property.</u></em>
6x - 10x - 120 = -4x - 24
<em><u>Add 10x to both sides.</u></em>
6x - 120 = 6x - 24
<em><u>Cancel like terms.</u></em>
<em>Add 24 to both sides.</em>
-96 ≠ 0.
This equation is incorrect, as -96 will never be equal to 0.
Answer: There are two solutions and they are
theta = 135
theta = 225
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Explanation:
Recall that x = cos(theta). Since the given cosine value is negative, this indicates x < 0. Theta is somewhere to the left of the y axis, placing it in quadrant 2 or quadrant 3.
It turns out there are two solutions, with one solution per quadrant mentioned above. Use the unit circle to find that the two solutions are:
theta = 135
theta = 225
You're looking for points on the unit circle that have x coordinate equal to x = -sqrt(2)/2. Those two points correspond to the angles of 135 and 225, which are in quadrants 2 and 3 respectively.
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I recommend using your calculator to note that
-sqrt(2)/2 = -0.70710678
cos(135) = -0.70710678
cos(225) = -0.70710678
The decimal values are approximate. Make sure your calculator is in degree mode. Because those three results are the same decimal approximation, this indicates that cos(135) = cos(225) = -sqrt(2)/2.
