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

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What is the length of a if a triangle has lengths of b=6.4cm and c=5.6cm with an angle A=107.9 degrees?


Expand: (x+3)(2x+4)


Make y the subject of the formula 3y-p=h(2+y)


simplify fully: (x^2+x-6)/(x^2-7x+10)