(
+
7
)
x
(
-
2
)
=
-
____________________
(
+
4
)
x
(
+
7
)
=
+
____________________
(
-
2
)
x
(
+
2
)
=
-
____________________
(
+
6
)
x
(
-
15
)
=
-
____________________
(
+
3
)
x
(
-
7
)
=
-
____________________
(
+
5
)
x
(
+
8
)
=
+
____________________
