Answer:
y²=4√2.x
Step-by-step explanation:
The focus is at (0,4) and directrix is y=x or x-y =0, for a parabola P.
The distance between the focus and the directrix of the parabola P is
=
{Since the perpendicular distance of a point (x1, y1) from the straight line ax+by+c =0 is given by
}
Let us assume that the equation of the parabola which is congruent with parabola P is y²=4ax
{Since the parabola has vertical directrix}
Hence, the distance between focus and the directrix is 2a =
, {Two parabolas are congruent when the distances between their focus and the directrix are same}
⇒ a=√2
Therefore, the equation of the parabola is y²=4√2.x (Answer)
Answer:
6.8% decrease
Step-by-step explanation:
a drop of 8% means that only 92% of 125 boys remained on honor roll from last year; .92 x 125 = 115
a drop of 5% means that only 95% of 80 girls remained on honor roll from last year; .95 x 80 = 76
total number of students on honor roll last year = 125 + 80 = 205
total number of students on honor roll this year = 115 + 76 = 191
percent of change = (191 - 205) ÷ 205 = -14/205 = -.068
-.068, which represents a 6.8% decrease