52_esquadro.html

<canvas width="600" height="400"></canvas>
<script>
    var canvas = document.querySelector('canvas');
    var brush = canvas.getContext('2d');

    //esquadro maior
    brush.fillStyle = 'black';
    brush.beginPath();
    brush.moveTo(50,50);
    brush.lineTo(50,400);
    brush.lineTo(400,400)
    brush.fill();

    //esquadro menor
    brush.fillStyle = 'white';
    brush.beginPath();
    brush.moveTo(100,175);
    brush.lineTo(100,350);
    brush.lineTo(275,350);
    brush.fill();
    
</script>