Solve like an equation,
You need x by itself.
Since x is on the denominator, multiply both sides by x to clear the fraction.
Tan 12 = 10/x
x Tan12 = 10
Divide both sides by Tan12
x = 10/(Tan12)
x = 47
This is one pathway to prove the identity.
Part 1
Part 2
Part 3
As the steps above show, the goal is to get both sides be the same identical expression. You should only work with one side to transform it into the other. In this case, the left side transforms while the right side stays fixed the entire time. The general rule is that you should convert the more complicated expression into a simpler form.
We use other previously established or proven trig identities to work through the steps. For example, I used the pythagorean identity 
in the second to last step. I broke the steps into three parts to hopefully make it more manageable.
The top right is the answer!
Answer: (x + 7)(x - 7)
Explanation: If a variable is taken to an even power, that variable is a perfect square. In this case, x² would therefore be a perfect square.
Since 49 is also a perfect square, what we have here is the difference of two squares. That can be factored as the product of two binomials one with a plus in the middle and one with a minus in the middle.
In the first position will be the factors of x² that are the same.
So we have <em>x</em> and <em>x</em>.
In the second position we will have the
factors of 49 that are the same, 7 and 7.
(x + 7)(x - 7) is your answer which is a factored version of x² - 49.
Answer:
(x + 2)² + (y - 1)² = 25
Step-by-step explanation:
radius: r² = (1 - (-3))² + (-2 - (-5))² = 16 + 9 = 25
r = 5
Circle: (x - h)² + (y - k)² = r²
center: (-2 , 1) h = -2 k = 1
(x + 2)² + (y - 1)² = 25
