<!DOCTYPE html>
<html lang="pt-br">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Esquadro</title>
</head>
<body>
<canvas width="600" height="400"></canvas>
<script>
let canvas = document.querySelector('canvas')
let context = canvas.getContext('2d')
context.beginPath();
context.moveTo(50, 50);
context.lineTo(50, 400);
context.lineTo(400, 400);
context.fill()
context.beginPath();
context.fillStyle = 'white';
context.moveTo(100,175);
context.lineTo(100, 350);
context.lineTo(275, 350);
context.fill()
</script>
</body>
</html>
