Examples
x=2x=2 , x=-2x=−2 , x=1x=1
Step 1
Since the roots of an equation are the points where the solution is 00, set each root as a factor of the equation that equals 00.
(x-2)(x-(-2))(x-1)=0(x−2)(x−(−2))(x−1)=0
Step 2
Step 2.1
Expand (x-2)(x+2)(x−2)(x+2) using the FOIL Method.
Step 2.1.1
Apply the distributive property.
(x(x+2)-2(x+2))(x-1)=0(x(x+2)−2(x+2))(x−1)=0
Step 2.1.2
Apply the distributive property.
(x⋅x+x⋅2-2(x+2))(x-1)=0(x⋅x+x⋅2−2(x+2))(x−1)=0
Step 2.1.3
Apply the distributive property.
(x⋅x+x⋅2-2x-2⋅2)(x-1)=0(x⋅x+x⋅2−2x−2⋅2)(x−1)=0
(x⋅x+x⋅2-2x-2⋅2)(x-1)=0(x⋅x+x⋅2−2x−2⋅2)(x−1)=0
Step 2.2
Simplify terms.
Step 2.2.1
Combine the opposite terms in x⋅x+x⋅2-2x-2⋅2x⋅x+x⋅2−2x−2⋅2.
Step 2.2.1.1
Reorder the factors in the terms x⋅2x⋅2 and -2x−2x.
(x⋅x+2x-2x-2⋅2)(x-1)=0(x⋅x+2x−2x−2⋅2)(x−1)=0
Step 2.2.1.2
Subtract 2x2x from 2x2x.
(x⋅x+0-2⋅2)(x-1)=0(x⋅x+0−2⋅2)(x−1)=0
Step 2.2.1.3
Add x⋅xx⋅x and 00.
(x⋅x-2⋅2)(x-1)=0(x⋅x−2⋅2)(x−1)=0
(x⋅x-2⋅2)(x-1)=0(x⋅x−2⋅2)(x−1)=0
Step 2.2.2
Simplify each term.
Step 2.2.2.1
Multiply xx by xx.
(x2-2⋅2)(x-1)=0(x2−2⋅2)(x−1)=0
Step 2.2.2.2
Multiply -2−2 by 22.
(x2-4)(x-1)=0(x2−4)(x−1)=0
(x2-4)(x-1)=0(x2−4)(x−1)=0
(x2-4)(x-1)=0(x2−4)(x−1)=0
Step 2.3
Expand (x2-4)(x-1)(x2−4)(x−1) using the FOIL Method.
Step 2.3.1
Apply the distributive property.
x2(x-1)-4(x-1)=0x2(x−1)−4(x−1)=0
Step 2.3.2
Apply the distributive property.
x2x+x2⋅-1-4(x-1)=0x2x+x2⋅−1−4(x−1)=0
Step 2.3.3
Apply the distributive property.
x2x+x2⋅-1-4x-4⋅-1=0x2x+x2⋅−1−4x−4⋅−1=0
x2x+x2⋅-1-4x-4⋅-1=0x2x+x2⋅−1−4x−4⋅−1=0
Step 2.4
Simplify each term.
Step 2.4.1
Multiply x2x2 by xx by adding the exponents.
Step 2.4.1.1
Multiply x2x2 by xx.
Step 2.4.1.1.1
Raise xx to the power of 11.
x2x+x2⋅-1-4x-4⋅-1=0x2x+x2⋅−1−4x−4⋅−1=0
Step 2.4.1.1.2
Use the power rule aman=am+naman=am+n to combine exponents.
x2+1+x2⋅-1-4x-4⋅-1=0x2+1+x2⋅−1−4x−4⋅−1=0
x2+1+x2⋅-1-4x-4⋅-1=0x2+1+x2⋅−1−4x−4⋅−1=0
Step 2.4.1.2
Add 22 and 11.
x3+x2⋅-1-4x-4⋅-1=0x3+x2⋅−1−4x−4⋅−1=0
x3+x2⋅-1-4x-4⋅-1=0x3+x2⋅−1−4x−4⋅−1=0
Step 2.4.2
Move -1−1 to the left of x2x2.
x3-1⋅x2-4x-4⋅-1=0x3−1⋅x2−4x−4⋅−1=0
Step 2.4.3
Rewrite -1x2−1x2 as -x2−x2.
x3-x2-4x-4⋅-1=0x3−x2−4x−4⋅−1=0
Step 2.4.4
Multiply -4−4 by -1−1.
x3-x2-4x+4=0x3−x2−4x+4=0
x3-x2-4x+4=0x3−x2−4x+4=0
x3-x2-4x+4=0x3−x2−4x+4=0