Notes

Sunday, September 7, 2014

MATH PROLEMGood old st. Nick needs your help getting from Andria's house to Tong's house on Xmas eve. Of course that means rooftop to rooftop. with...

I can not draw you a picture. However I will describe how
you could draw the parabola.


We will assume that the tree
is the y-axis.


Also,  the roof meets
the tree at the origin point (0,0)


The tree stands 190 feet
above the roof.


Then the maximum of the parabola is the
point ( 0, 190)


Now the distance between the roofs will
represent the distance on the x-axis.


The distance is 300
feet.


The tree is half way between the
roofs.


==> The roofs if 150 feet from the origin
point if opposite directions.


Then the points ( 150, 0) and
( -150, 0) represent the roofs.


Then, The parabola is
facing down .


==> y = -ax^2 +
b


We will substitute the point (0,
190)


==> y(0) = b =
190


==> y = -ax^2 +
190


Now we will substitute with (150,
0)


==> y( 150)= -a(150)^2 + 190 =
0


==> a = 190/ 150*150 =
19/2250


==> y= (-19/2250) x^2 +
190

at September 07, 2014
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