What exactly do you need help with with this topic<span />
> multiply the second equation by 2 and add it to the first equation.
2(-6x - 7y = -10)
-12x -14y = -20
8x + 14y = 4
-12x - 14y = -20
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- 4x + 0 = - 16
x = -16/-4
x = 4
> use x = 4 in either equation to find y
8(4) + 14y = 4
32 + 14y = 4
14y = 4 - 32
14y = -28
y = -28/14
y = -2
4 over 12 times 8 over 20
= 4/12 * 8/20 ....( 4/12 = 1/3; 8/20 = 2/5)
=1/3 * 2/5
=2/15
Answer:
where is the graph????
Step-by-step explanation:
Given:
There are given that the cos function:

Explanation:
To find the value, first, we need to use the half-angle formula:
So,
From the half-angle formula:

Then,
Since 105 degrees is the 2nd quadrant so cosine is negative
Then,
By the formula:

Then,
Put the value of cos210 degrees into the above function:
So,

Final answer:
Hence, the value of the cos(105) is shown below: