Use the Quadratic Formula to Solve to 3 s.f.
Question 1:
x
2
−
7
x
−
7
=
0
x
=
7.89
or
-0.887
Question 2:
x
2
+
9
x
+
7
=
0
x
=
-0.86
or
-8.14
Question 3:
x
2
+
12
x
−
6
=
0
x
=
0.481
or
-12.5
Question 4:
5
x
2
+
8
x
+
2
=
0
x
=
-0.31
or
-1.29
Question 5:
4
x
2
−
4
x
−
1
=
0
x
=
1.21
or
-0.207
Question 6:
4
x
2
+
15
x
+
6
=
0
x
=
-0.455
or
-3.29
