A computer technician charges \( \$ 190 \) for a \( 3 \) -hour appointment and \( \$ 370 \) for a \( 7 \) -hour appointment. Which of these represents a linear function that models the charge, \( y \) , for hiring the technician for \( x \) hours?
А \( y = 55 x + 45 \)
В \( y = 45 x + 55 \)
C \( y = 45 x + 190 \)
D \( y = 55 x + 190\)
B) y=45x+55
9. A board game company models the profit on its latest board game using the quadratic relation
\( P = - 2 x ^ { 2 } + 28 x - 90 , \) where \( x \) is the number of games it produces in hundred thousands and \( P \) is the profit in millions of dollars.
a) What are the break-even points for the company?
b) What is the maximum profit that the company can earn?
The graph of \( y = f ( x ) \) is stretched horizontally by a factor of \( 5 \) , and reflected in the \( x \) -axis. What is the equation of the image graph in terms of \( f \) ?
A. \( y = - f ( 5 x ) \) C. \( y = - f ( \frac { 1 } { 5 } x ) \)
B. \( y = - \frac { 1 } { 5 } f ( x ) \) D. \( y = - 5 f ( x )\)
