Very Important Question

[tralalala]

well... its like this:

were learning about parabulas in maths... (multiplication of functions)

so, how do you draw and explaine how you solve the following parabula: (2x-4)(5x+15)?????


thanks guys... please, i need the answer by tomorrow morning


Rafi

[SillyRumours]

digging into brain, duhhherrrm - i think you solve it by finding where the line crosses the x-axis, and you would do that by putting the equation into the form ax"+bx+c (" that's a superscript 2 by the way)

to draw it you need to work out where the y-intercept is, and i can't remeber how :(

[fred devliegher]

1 (2x-4)(5x+15) = 10x²-20x+30x-60
= 10x²+10x-60

2 Found my old TI-83, and you're in luck : I made a little program that'll do the rest for ya : the graph intersects the X-axis (Y=O) at x=-3 and x=2

Explaination : B²-(4AC) -> discriminant, here that would be D=2500
(-B[+/-]root(D))/(2A) => intersect points

You're welcome :)

[vidcc]

oh hum :rolleyes: yet another student that doesn't want to put his/ her own research time in :blink: