The vertex is exactly half way between directrix and focus. In this case the vertex is (8,-7)
(h,k)
P is the distance between the vertex and either the directrix or focus, in this case p = 1.
a = 1/(4p) or 1/(4*1) or 1/4
write the equation in vertex form
y = a(x-h)^2 + k
y = 1/4(x-8)^2 -7
To figure out the cost per cookie, divide $2.49 by 3. The cost per 1 cookie (column 1) would be .83 cents.
To figure out the cost of 20 cookies, multiply 20 x .83 cents. The answer is 20 cookies would cost $16.60
To figure out how many cookies would cost $145,25, divide $145.25 by .83 cents. The answer is 175 cookies would cost $145.25
71 %
Calculate score for each paper, total them and convert to a percentage.
Paper 1 : mark = 0.65 × 120 =78
Paper 2 :mark = 0.8 ×80 = 64
Total mark = (78 + 64)/200 =142/200
Percentage score = 142/200 × 100 % = 71 %
