void Draw(Graphics g, double cb, double ck, double a, double h)
{
var dashPen = new Pen(Brushes.Black)
{
DashPattern = new float[] { 10, 5 }
};
g.DrawLine(Pens.Black, 400, 100, 200, 500);
g.DrawLine(Pens.Black, 200, 500, 500, 500);
g.DrawLine(Pens.Black, 400, 100, 500, 500);
g.DrawLine(Pens.Black, 500, 500, 600, 400);
g.DrawLine(Pens.Black, 400, 100, 600, 400);
g.DrawLine(Pens.Black, 300, 400, 600, 400);
g.DrawLine(dashPen, 400, 100, 300, 400);
g.DrawLine(dashPen, 300, 400, 200, 500);
g.DrawLine(dashPen, 400, 100, 400, 450);
var font = new Font(FontFamily.GenericSansSerif, 12, FontStyle.Italic);
g.DrawString("h", font, Brushes.Black, 380, 320);
g.DrawString("a", font, Brushes.Black, 360, 500);
g.DrawString($"На бетон {(1 / 3d * a * a * h * h) * cb:#,##0.00} руб.", SystemFonts.DefaultFont, Brushes.Black, 440, 100);
g.DrawString($"На облицовку {a * Math.Sqrt(a * a + 4 * h * h) * ck:#,##0.00} руб.", SystemFonts.DefaultFont, Brushes.Black, 440, 120);
}