In each of the following x and y vary directly with each other . Find the constant of variable .
(i) y = 3x (ii) 2x=3y
(iii) 9x=y (iv) y = 2x

The lines x+3y-1=0 and x-4y=0 intersect each other. Find their point of intersection.

Observe the following tables and find if x and y vary directly or indirectly . (a)

Find the values of x and y if : 3x + (2x-y)i= 6-3i .

Find the coefficient of x^6 y^3 in (x+2y)^9 .

If the circles x^2+y^2=9 and x^2+y^2+8y+c=0 touch each other, then c is equal to:

For which of the following, y can be a function of x, (x in R, y in R) ? {:((i) (x-h)^(2)+(y-k)^(2)=r^(2),(ii)y^(2)=4ax),((iii) x^(4)=y^(2),(iv) x^(6)=y^(3)),((v) 3y=(log x)^(2),""):}

Show that the following curves cut each other orthogonally: y = x^3 and 6y = 7-x^2

Find the greatest value of x^3y^4 if 2x + 3y = 7 and x>=0,y>=0 .