How to find the coordinates?

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2 Answers
Feb 25, 2018

(x,y)=(49,2)

Explanation:

4y=9x+4
y2=9x
All we need to do is to solve the system of equations, the solutions are the required points, so:
9x=4y4
x=4y49
y2=94y49
y24y+4=0
(y2)2=0
y=2
x=49
thus the required coordinated are:
(x,y)=(49,2)

Feb 25, 2018

(x,y)(49,2)

Explanation:

4y=9x+4(1)

y2=9x(2)

from equation (1)x9x=4y4(3)

substitute 9x=4y4 in equation (2)

y2=4y4rearrange and equate to zero

y24y+4=0

(y2)2=0y=2

substitute y=2 in equation (3)

9x=84x=49

point of contact =(49,2)
graph{(y-9/4x-1)(y^2-9x)=0 [-10, 10, -5, 5]}