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

4937 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Solve the following simultaneous equations: x^2 + 2y = 9, y = x + 3


Find the co-ordinates where the curve y= 2x^2 + 7x + 3 crosses the x axis


PQRS is a parallelogram with P->Q=a and P->S=b. Find S->Q in terms of a and b. N is a point between S and Q, where SN:NQ is 3:2, find N->R


Find the turning point of the curve whose equation is y = (x-3)^2 + 6.


We're here to help

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

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning