The equation of a quadratic curve is y=x^2+ax+b. The points (6,-4) and (4,-6) lie on this curve. Find the co-ordinates of the turning point of the curve.

If y=x^2 + ax + b is the equation for the curve, then the points which lie on the curve must satisfy this equation.Inputing the points into the equation gives:-4 =6^2+6a+b -6=4^2+4a+bNow solve simultaneously to find a and b. Eliminate b by subtracting 2. from 1.1. - 2. : 2 = 20 +2a. Rearranging gives a = -9Substituting a =-9 into any of the equations gives b = =14. So the equation of the curve is y=x^2-9x+14. Completing the square to find the turning point gives: (x-(9/2))^2-(81/4)+14 which simplifies to (x-(9/2))^2-25/4. So co-ordinates of turning point is: (9/2,-25/4)

Answered by Sena A. Maths tutor

3445 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve the inequality x^2 – x < 6


Simplify (2sin45 - tan45)/(4tan60) and leave your answer in the form of (sqrt(a)-sqrt(b))/c


Write x² + 4x -16 = 0 in the form (x+a)² - b = 0. Solve the equation giving your answer in surd form as simply as possible.


A circular table top has diameter 140 cm. Calculate the area of the table top in cm² , giving your answer as a multiple of π.


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo
Cookie Preferences