<instructions>
<p>
Let <m>\vec{x}</m> be represented by the red arrow,
and <m>A\vec{x}</m> by the grey arrow,
for some particular <m>2\times 2</m> matrix <m>A</m>.
Drag the <em>tip</em> of the red arrow to see the grey arrow change.
</p>
</instructions>
Let \(\vec{x}\) be represented by the red arrow, and \(A\vec{x}\) by the grey arrow, for some particular \(2\times 2\) matrix \(A\text{.}\) Drag the tip of the red arrow to see the grey arrow change.
