Step-by-step explanation:
1.


Therefore,

2.


Use the identity

We chose the negative value of the cosine because of the condition where cot y > 0. Otherwise, choosing the positive root will yield a negative cotangent value. Now that we know the sine and cosine of y, we can now solve for the tangent:

3. Recall that sec x = 1/cos x, therefore cos x = 5/6. Solving for sin x,

Solving for tan x:

Parenthesis according to the PEMDAS rule
So
7(x - 4) = 84
Would be
7x -28 = 84
Hope this helped :)
Answer:
s = 5.1
Step-by-step explanation:

Multiply both sides of the equation by 10

Expand

Subtract 28 from both sides

Simplify

Divide both sides of the equation by 10

Simplify

What two factors of 48 add up to -16? -4 and -12
So the factored form would be (x-4)(x-12)