Answer:
15 blocks
Step-by-step explanation:
We can use the Pythagorean theorem to solve the right triangle
a^2 + b^2 = c^2 where a and b are the legs and c is the hypotenuse
12^2 + 9^2 = h^2
144+81 = h^2
225= h^2
Taking the square root of each side
sqrt(225) = sqrt(h^2)
15 = h
Yay
so
this is going to be
(x-h)^2=4p(y-k)
(h,k) is the vertex
p is the distance from the vertex to the focus and the vertex to directix
half of the distance between directix and focus is p
if the directix is above the focus, p is negative
if the directix is below the focus, p is positive
so
we see
y=15/8 is the directix
focus is above directix (p is positive)
it is 2/8 or 1/4 above it
so
half of 1/4 is 1/8
p=1/8
the vertex is 1/8 below vertex so it is it at (-4,16/8) or (-4,2)
the equation is
(x-(-4))^2=4(1/8)(y-2) or
(x+4)^2=4(1/8)(y-2) is the equation
An other name is skip counting
