“BOTTOMS UP”

Factoringax2 + bx + c

6X2 + 13X + 6Step 1: multiply the constant (c) term by

the coefficient (a), of the leading term Constant is 6 Leading term is 6Therefore 6 * 6 is 36

6X2 + 13X + 6 Step 2: Rewrite the equation by replacing

the constant with the number in step 1, and remove the leading coefficient.

x2 + 13x + 36

Step 3: Factor the new equation from

step 2: x2 + 13x +36

(x + 4)(x + 9)

(X + 4)(X + 9)

Step 4: Divide each constant term in the factored form by the original coefficient of the leading term.

Original coefficient of the leading term: 6

Then reduce the fractions:

Step 5: Now we use the “bottoms up”

method- Move the denominator into the numerator to get:

Check it- use FOIL:

Remember you may check some

equations using graphing calculator- type in the equation in y = and find where it crosses the x-axis. Not all equations cross the x-axis. This particular one crosses at x = -2/3 and x = -3/2. Look at these solutions and the end result of step 4, and then look at step 5. Factoring leads to solutions, the zeros, the roots.

10X2 - X - 3Step 1: multiply the constant (c) term by

the coefficient (a), of the leading term Constant is -3Leading term is 10Therefore -3 * 10 is -30

10X2 - X - 3 Step 2: Rewrite the equation by replacing

the constant with the number in step 1, and remove the leading coefficient.

x2 - x - 30

X2 - X - 30

Step 3: Factor the new equation from step 2: x2 - x - 30

(x + 5)(x - 6)

(X + 5)(X - 6)

Step 4: Divide each constant term in the factored form by the original coefficient of the leading term.

Original coefficient of the leading term: 10

(x + 5)(x - 6)

10 10

Then reduce the fractions:

(x + 1)(x - 3) 2 5

Step 5: Now we use the “bottoms

up” method- Move the denominator into the numerator to get:

(2x + 1)(5x – 3)

(x + 1)(x - 3) 2 5

Check it- use FOIL:

10x2 -6x + 5x – 3

10x2 - x – 3

(2x + 1)(5x – 3)

YOU TRY!6x2 - 2x – 28

Step 1: multiply the constant (c) term by the coefficient (a), of the leading term

 Constant is -28Leading term is 6Therefore 6 * -28 is -168

6X2 - 2X – 28

Step 2: Rewrite the equation by replacing the constant with the number in step 1, and remove the leading coefficient.

x2 -2x -168

Step 3: Factor the new equation

x2 -2x -168

( x -14 )(x +12 )

Factors of -168

Sum of factors

-2, -84 no-4, 42 no-8, 21 13-12, 14 2Switch-14, 12 -2

( X -14 )(X +12 )

Step 4: Divide each constant term in the factored form by the original coefficient of the leading term.

Original coefficient of the leading term: 6

( x -14 )(x +12 ) 6 6

( X -14 )(X +12 ) 6 6

Then reduce the fractions:

( x -7 )(x +2 ) 3 1

Step 5: Now we use the “bottoms up”

( 3x -7 )(x +2 )Check your answer with factoring (your choice).

Conversation with a caution6x2 - 2x – 28

Purpose of factoring

QUICK STEPS!Step 1: multiply (c) (a), Step 2: Rewrite the equation by replacing

the constant with the number in step 1, and remove the leading coefficient.

Step 3: Factor the new equationStep 4: Divide each constant term in the

factored form by the original coefficient of the leading term and then reduce the fractions:

Step 5: Now we use the “bottoms up”