diff --git a/Circle.py b/Circle.py
index f0c33d1..f0b18d1 100644
--- a/Circle.py
+++ b/Circle.py
@@ -1,3 +1,22 @@
 
 class Circle(Shape):
-    pass
+    def __init__(self, x, y, r):
+        self.vars = [x, y, r]
+
+    def nVars(self):
+        return len(self.vars)
+
+    def nPts(self):
+        return 5
+
+    def toEqu(self, ptNum):
+        if ptNum == 0:
+            return ([1, 0, 0], [0, 1, 0])
+        elif ptNum == 1:
+            return ([1, 0, 1], [0, 1, 0])
+        elif ptNum == 2:
+            return ([1, 0, 0], [0, 1, 1])
+        elif ptNum == 3:
+            return ([1, 0, -1], [0, 1, 0])
+        elif ptNum == 4:
+            return ([1, 0, 0], [0, 1, -1])
diff --git a/Line.py b/Line.py
index 0086ccb..b576365 100644
--- a/Line.py
+++ b/Line.py
@@ -1,7 +1,16 @@
 
 class Line(Shape):
     def __init__(self, x0, y0, x1, y1):
-        self.x0 = x0
-        self.y0 = y0
-        self.x1 = x1
-        self.y1 = y1
+        self.vars = [x0, y0, x1, y1]
+
+    def nVars(self):
+        return len(self.vars)
+
+    def nPts(self):
+        return 3
+
+    def toEqu(self, ptNum):
+        if ptNum == 0:
+            return ([1, 0, 0, 0], [0, 1, 0, 0])
+        elif ptNum == 1:
+            return ([0, 0, 1, 0], [0, 0, 0, 1])