We know that
Any point <span>(x,y)</span> on the parabola is equidistant from the focus and the directrix
Therefore,
focus (0,4) and directrix of y=2
<span>√[<span>(x−0)</span></span>²+(y−4)²]=y−(2)
<span>√[x</span>²+(y-4)²]=y-2
x²+(y-4)²=(y-2)²
x²+y²-8y+16=y²-4y+4
x²=4y-12-----> 4y=x²+12----->y= (x²/4)+3
the answer is
y= (x²/4)+3
1. 2/7
2. 2/15
3. 5/24
4. 2/11
To find his age 4 years ago, you need to subtract 4 from his current age.
His current age is Y, so his age 4 years ago is: y - 4