Eliminate the parameter t & graph (trig)

[maskofeowyn]

x=-cost & y=cost

I know that cost = -x and that cost = y. I know I need to use a trig function to change these so that I can solve it so that I can graph it. I'm confused as to which function to use. Please help! Thank you.

 

[pka]

Surely you can see that: \(\displaystyle y = - x.\)

 

[soroban]

Surely you can see that: \(\displaystyle y = - x.\) . . . Correct!

But since \(\displaystyle \,-1\:\leq \:\cos t \:\leq\:1,\;x\) and \(\displaystyle y\) are similarly limited.

The graph is a line segment from \(\displaystyle (-1,1)\) to \(\displaystyle (1,-1)\)