17 Mark for Review An auditorium has seats for 1,400 people. Tickets to attend a show at the auditorium currently cost \( \$ 6.00 \). For each \( \$ 1.00 \) increase to the ticket price, 100 fewer tickets will be sold. This situation can be modeled by the equation \( y=-100 x^{2}+800 x+8,400 \), where \( x \) represents the increase in ticket price, in dollars, and. represents the revenue, in dollars, from ticket sales. II this equation is graphed in the \( x y \)-plane, at what valui of \( x \) is the maximum of the graph? (A) 4 (B) 6 (C) 8 (D) 14

Make \( w \) the subject of the formula \[ y=3 w-a \]

Sally would like to decorate her window-sill in her kitchen with mosaic tiles. The mosaic tiles are \( 20 \mathrm{~cm} \times 20 \mathrm{~cm} \) and cost R6,20 per centimetre. Calculate the cost of tiling her window-sill with mosaic tiles, if her window-sill measures 720 mm .

(3) \( 2 p+q=30 \) \( p=2 q \)

20. What is the difference between the biggest and the smallest fraction among \( \frac{2}{3}, \frac{3}{4}, \frac{4}{5} \) and \( \frac{5}{6} \) ? \( \begin{array}{llll}\text { (a) } \frac{1}{6} & \text { (b) } \frac{1}{12} & \text { (c) } \frac{1}{20} & \text { (d) } \frac{1}{30}\end{array} \)

a función racional \( f(x)=\frac{3 x^{2}+5 x+1}{(x+1)\left(x^{2}+3\right)} \). Al realizar la descomposición en fraciones parciales tenemos la siguiente forma.