Quadratic Equations (Factoring Method) How to solve quadratic equation of the form ax2 + bx + c = 0 with factoring If the given quadratic equation can be factored, the equations can be solved as follows: If ax 2 + bx + c = ( px + q )(rx + s ) ax 2 + bx + c = 0
( px + q )(rx + s ) = 0
px + q = 0 rx + s = 0
x=
q p s r
EXERCISE 1 1. Solve the following quadratic equations using the factoring method: (a) 2 x 2 + 7 x + 3 = 0
(b) 3 x 2 + 4 x + 1 = 0
Ans: x =
and
Ans: x =
.
(c) 2 x 2 + x 4 = 0
and
(d) 6 x 2 7 x + 2 = 0
Ans: x =
and
Ans: x =
.
(e) x 2 5 x + 3 = 0
and
.
and
.
(f) 6 x 2 + 5 x 6 = 0
Ans: x =
and
.
Ans: x =
.
2. Solve the following quadratic equations using the factoring method: (a) 14 x 2 29 x 12 = 0
(b) x 2 6 x + 9 = 0
Ans: x =
and
Ans: x = 3 and
.
.
3. Solve the following quadratic equations using the factoring method: (a) x 2 81 = 0
(b) x 2 25 = 0
Ans: x = 9 and
Ans: x =
and
.
Ans: x = 1.73 and
.
.
(c) x 2 2 = 0
(d) x 2 3 = 0
Ans: x = 1.414 and
.
(e) x 2 + 25 = 0
(d) x 2 + 1 = 0
Ans:
Ans:
.
..
4. Solve the following quadratic equations using the complete square method: (a) x 2 2 x = 0
(b) x 2 5 x = 0
Ans: x = 2 and
.
Ans: x = 5 and
.
EXERCISE 2 1. Solve the following quadratic equations using the complete square method: (a) 2 x 2 + 7 x + 3 = 0
(b) 3 x 2 + 4 x + 1 = 0
Ans: x =
and
.
(c) 2 x 2 + x 4 = 0
Ans: x =
and
.
Ans: x =
and
..
Ans: x =
and
..
Ans: x =
and
..
(d) 6 x 2 7 x + 2 = 0
Ans: x =
and
.
(e) x 2 5 x + 3 = 0
(f) 6 x 2 + 5 x 6 = 0
Ans: x =
and
..
(d) x 2 81 = 0
(d) x 2 5 x = 0
Ans: x =
and
.