Alright,
directix is y=something so it opens down or up
we use
(x-h)²=4p(y-k)
the vertex is (h,k)
and p is distance from focus to vertex
if focus is above directix, p is positive
if focus is below directix, p is negative
so we gts
focus=(1,1)
directix is y=-1
1>-1
focus is above
oh, vertex is in middle of focus and directix
so
beteeen (1,1) and y=-1 is, hmm
that is a distance of 2 vertically
2/2=1
1 down from (1,1) is (1,0)
vertex is (1,0)
p=1
so
(x-1)²=4(1)(y-0)
solving for y to get into f(x)=something form
(x-1)²=4y
y=1/4(x-1)²
f(x)=1/4(x-1)²
4th option
Answer:
i think it's b sorry if it's wrong
Step-by-step explanation:
The tangent of an angle is the ratio of the opposite side to the adjacent side.
... tan(45°) = (height above eye level)/(20 m)
... height above eye level = (20 m)·tan(45°) = (20 m)·1 = 20 m
_____
Eye level is 1.7 m above ground, so the height of the flagpole above ground is
... height of pole = height above eye level + height of eye level
... height of pole = 20 m + 1.7 m = 21.7 m