Find x and y intercepts using algebra for y = -x^2/8 + 9x/8 + 5/4

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Luffy

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y = -x2/8 + 9x/8 + 5/4

I need to use algebra to find the x and y intercepts of a parabola using the above quadratic equation but I am not sure where to begin.

I know I need to put the x and y coordinates at 0 and then factorise, but do I need to simplify the equation first?

Would I even be right in stating that the y intercept is (0,5/4)?

Any help or direction to get me started would be much appreciated.
 
Luffy said:
y = -x2/8 + 9x/8 + 5/4

I need to use algebra to find the x and y intercepts of a parabola using the above quadratic equation but I am not sure where to begin.

I know I need to put the x and y coordinates at 0 and then factorize, but do I need to simplify the equation first?

Would I even be right in stating that the y intercept is (0,5/4)?

Any help or direction to get me started would be much appreciated.
Click to expand...

Go to:

http://www.purplemath.com/modules/intrcept.htm

for a quick review.

at y-intercept → x = 0 → y = -02/8 + 9*0/8 + 5/4 → y = 5/4

at x-intercept → y = 0 → 0 = -x2/8 + 9x/8 + 5/4

multiplying both sides by 8 (to eliminate fraction and pesky negative leading coefficient), we get,

x2 - 9x - 10 = 0 ....... now factorize and continue.....
 
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