For what values of k does the line y=kx-1 have two distinct points of intersection with the circle (x-2)^2+(y-3)^2=2?

sub y=kx-1 into circle equation, get (k^2+1)x^2-(8k+4)x+18=0for 2 distinct solutions need b^2-4ac>0, ie -8k^2+64k-56>0iff k^2-8k+7<0complete the square: intersections of equation in k satisfy(k-4)^2=9 so inequality satisfied when 1<k<7. strict inequality for distinct intersection

CB
Answered by Christopher B. Maths tutor

4837 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

factorise: 3x^2+13x-30


Make x the subject of the following formula: 2x-4=2y.


Change of subject question. Make 'a' the subject of the formula v = u + at.


Shape ABCD is a parallelogram. Y is the mid-point of AB and Z is on BC such that BZ=1/2ZC. Given that AB=a and BC=b, describe, in terms of a and b: a) AC b)CY c)YZ


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences