Falling Behind in Studies? Join Our Performance Improvement Batch. Enroll For Free
One of our academic counsellors will contact you within 1 working day.
Click to Chat
1800-1023-196
+91-120-4616500
CART 0
Use Coupon: CART20 and get 20% off on all online Study Material
Welcome User
OR
LOGIN
Complete Your Registration (Step 2 of 2 )
find the value of k in which straight line 3x+4y=k touches the circle x^2+y^2=10x
it''s quite simple simply first put the eqn of line in the curve 3x+4y=k (k-3x)/4=y put this in the curve x^2+(k-3x/4)^2=10x 16x^2+k^2+9x^2-6kx=160x 25x^2+x(-6k-160)+k^2=0 now this quadratic equation will have only one solution because this line touches it at only one point hence the value of x should come out only one. so Discriminant of this eqn is 0(for same roots) 36k^2+25600+1920k-4*25*k^2=0 hence k=40,-10 Please rate if it helped
it''s quite simple
simply first put the eqn of line in the curve
3x+4y=k
(k-3x)/4=y
put this in the curve
x^2+(k-3x/4)^2=10x
16x^2+k^2+9x^2-6kx=160x
25x^2+x(-6k-160)+k^2=0
now this quadratic equation will have only one solution because this line touches it at only one point hence the value of x should come out only one.
so Discriminant of this eqn is 0(for same roots)
36k^2+25600+1920k-4*25*k^2=0
hence k=40,-10
Please rate if it helped
PLZZZZZZZZZZZZZZZZZ APPROVE THE ANSWER IF YOU ARE SATISFIED BY CLIKING THE YES BUTTON ......................
Post Question
Dear , Preparing for entrance exams? Register yourself for the free demo class from askiitians.
points won -