There actually isn't anything to 'work'. There's no question there.
The function simply describes the relationship between two numbers.
It says that whatever you pick for the first number, the second number is
(-4 times the square of the first one) plus (7 times the first one) plus (6) .
Your teacher may have assigned you something to do with the function,
like draw the graph of it, or find its maximum value (2.9375), or find where
it crosses the x-axis (2.381 and -0.63) or the y-axis (6).
But we can't tell what you've been assigned to do with it. The function alone,
just as you've posted it, isn't asking a question, and doesn't call for any work.
Answer:
X=23
Step-by-step explanation:
You should know that a triangle =180 degrees
Add all your angles together and =180
66+2x+3+3x-4=180
add similar terms
5x+65=180
Move your 65 to the other side
5x=115
x=23
(Optional)
to check if your answer is right substitute your x and add all angles together you should get 180 degrees.