Answer:
11 dimes, 17 nickels
Step-by-step explanation:
d + n = 28, put one variable by itself on a side, d = 28 - n
.10d + .05n = 1.95
Sub the first equation into the second
.10(28 - n) + .05n = 1.95
2.8 - .10n + .05n = 1.95
2.8 - .05n = 1.95
-.05n = -0.85
n = 17 nickels
d + 17 = 28
d = 11 11 dimes
we are given with the data of a parabola with vertex at (2, 2) and directrix at y = 2.5. the formua should be ax^2 + b x + c = y because of the directrix.
(x-h)^2 = 4a (y-k)
(x-2)^2 =4a (y-2)
a is the equidistant distance from focus to vertex and from vertex to directrix that is equal to -0.5
then the answer is
(x-2)^2 =-0.5*4 (y-2)
x2 - 4x + 4 = -2y +4
x2-4x+2y = 0
answer is C
