If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)

Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie

Hi there,
There is an issue with role permissions that is being worked on at the moment.
If you are having trouble with access or permissions on regional forums please post here to get access: https://www.boards.ie/discussion/2058365403/you-do-not-have-permission-for-that#latest

ANOTHER silly maths question..

We · 2009-04-10 15:11:56

ye so, functions and graphs this time.. Now this should be easy enough.. but I'm silly, so apparently not so easy for me ;p The graph of the function f(x) = x^2 + bx + c is shown.. Find the values of b and c... if the graph isn't clear enough, the curve goes through (0,0) and (5,0) thanks homies ;)

10-04-2009 3:11pm

#1

We

Users Awaiting Email Confirmation Posts: 284 ✭✭

Join Date: February 2009

Posts: 242

ye so, functions and graphs this time..
Now this should be easy enough.. but I'm silly, so apparently not so easy for me ;p

The graph of the function f(x) = x^2 + bx + c is shown..
Find the values of b and c...

if the graph isn't clear enough, the curve goes through (0,0) and (5,0)

thanks homies

0

Comments

#2 10-04-2009 3:18pm

Jack Sheehan

Registered Users, Registered Users 2 Posts: 1,693 ✭✭✭

Join Date: July 2006

Posts: 1645

Put in the values, form two equations and use similtanious equations to get a result?

0
#3 10-04-2009 3:21pm

We

Users Awaiting Email Confirmation Posts: 284 ✭✭

Join Date: February 2009

Posts: 242

:facepalm: ... thanks jack, dunno why I didn't sub in both x and y values.. I just subbed in the x value for both points and when it didn't look how I expected it to, I came here ;p laziness I guess ^_^

0
#4 10-04-2009 3:22pm

Jack Sheehan

Registered Users, Registered Users 2 Posts: 1,693 ✭✭✭

Join Date: July 2006

Posts: 1645

No Worries.

0
#5 10-04-2009 3:25pm

383Ger

Registered Users, Registered Users 2 Posts: 63 ✭✭

Join Date: February 2009

Posts: 54

The curve x^2+bx+c cuts the x-axis at 0 and 5, thus x=0 and x=5 will solve the equation x^2+bx+c=0

Substituting:
(0)^2+b(0)+c=0
0+0+c=0
c=0

Now substituting x=5
(5)^2+b(5)+0=0
25+5b=0
5b=-25
b=-5

0
#6 10-04-2009 3:27pm

We

Users Awaiting Email Confirmation Posts: 284 ✭✭

Join Date: February 2009

Posts: 242

just did it there and got same answer, cheers lads

0
Advertisement