Find System of 2 Equations in 2 Vars for x=t, y=3t-4

bbdynamite
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Homework Statement


Find a system of two equations in two variables, x and y, that has the solution set given by the parametric representation x=t and y=3t-4, where t is any real number.


Homework Equations


x=t and y=3t-4, where t is any real number


The Attempt at a Solution


y=3x-4 which means that x=(y+4)*1/3. But that is still only one equation and I can't figure out what the other one is. If there are two equations with two unknowns, couldn't the solutions be precise numbers? Since the solution given is parametric, I think there is only one equation in two variables. However, this does not satisfy the question's requirements. What is going on?
 
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bbdynamite said:

Homework Statement


Find a system of two equations in two variables, x and y, that has the solution set given by the parametric representation x=t and y=3t-4, where t is any real number.

Homework Equations


x=t and y=3t-4, where t is any real number

The Attempt at a Solution


y=3x-4 which means that x=(y+4)*1/3. But that is still only one equation and I can't figure out what the other one is. If there are two equations with two unknowns, couldn't the solutions be precise numbers? Since the solution given is parametric, I think there is only one equation in two variables. However, this does not satisfy the question's requirements. What is going on?

I agree with you. It's probably just a mistake in the problem. If you want a second equation you could always suggest something like x=x or something else redundant. But that's pretty pointless.
 
OK thanks for confirming my thought.
 
Two independent equations in x and y will necessarily have a unique solution, not an infinite set of equations as you are given. Yes, x and y must satisfy y= 3x- 4 which I would write as 3x- y= 4. A second equation must be a multiple of that, say, 9x- 3y= 12.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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