# How to make points on two curves having same x-coordinate change?

Math123 shared this question 4 years ago

Pls see attached.

I have two curves. Draw one point on each curve how make these two points x-coordinate always same. As i move one point the same way x-coordinate of second point change. 3

May be B=(x(A), g(x(A))) 1

Thanks frndmrsl , This way B = (x(A),g(x(A))) . When moving A can move B, not B moving. Is it possible both way point moving. 4

It's normal, because in this way the point B becomes dependant from point A.

Try to use a slider "t" and define A=(t,f(t)) and B=(t,g(t)) 1

Yes, the slider works fine. As an alternative you could do the following:

• Place a point on the x-axis. (point C)
• Construct a line through C that is perpendicular to the x-axis. (line h)
• Find the intersection of h and f or redefine A to be Intersect(h, f).
• Find the intersection of h and g or redefine B to be Intersect(h, g).

Then as you drag C along the x-axis, the two points on the curves move together. 1

see script of A and B points 1

@ alirezagholamian simple et en parfaite adéquation avec la question . Bravo . 