If we know that the blue angle is `MEASURE` degrees, what is the measure of the orange angle?

`MEASURE`

init({
range: [ [ -1, 5 ], [-1, 1] ]
});
graph.pl = new ParallelLines( 0, 0, 4, 0, 0 );
graph.pl.draw();
graph.pl.drawTransverse( ANCHOR );
graph.pl.drawAngle( KNOWN_INDEX, true );
graph.pl.drawAngle( UNKNOWN_INDEX, false, "#FFA500" );

What is the measure of the pink angle?

graph.pl.drawAngle( KNOWN_INDEX + 1, false, "#FF00AF" );

The pink and blue angles add up to 180 because they are adjacent and form a straight line.

`\color{#FF00AF}{\text{pink angle}}= 180^{\circ} - \color{#6495ED}{`

`MEASURE`^{\circ}} = \color{#FF00AF}{`180 - MEASURE`^{\circ}}

graph.pl.drawAngle( KNOWN_INDEX + 1, true, "#FF00AF" );

The pink and orange angles also add up to 180 because they are adjacent and form a straight line too.

`\color{#FFAF00}{\text{orange angle}}= 180^{\circ} - \color{#FF00AF}{`

`180 - MEASURE`^{\circ}} = \color{#FFAF00}{`MEASURE`^{\circ}}

graph.pl.drawAngle( UNKNOWN_INDEX, true, "#FFA500" );