Update Triangle.java

jshERP-boot/src/main/java/com/jsh/erp/utils/Triangle.java

@@ -4,6 +4,6 @@ public class Triangle extends Shape {
 	@Override
 	public double area(double length,double width) {
 	System.out.println ("triangle ~area");
-	return 1.0/2*length*width;
+	return length*width/2;
 }
 }