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3 votes
Simplify.
6x2x-8
9y2

User Tekkavi
by
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1 Answer

3 votes

6x3 - 89y2

Step by step solution :

Step 1 :

Equation at the end of step 1 :

((6 • (x2)) • x) - 89y2

Step 2 :

Equation at the end of step 2 :

((2•3x2) • x) - 89y2

Step 3 :

Trying to factor as a Difference of Cubes:

3.1 Factoring: 6x3-89y2

Theory : A difference of two perfect cubes, a3 - b3 can be factored into

(a-b) • (a2 +ab +b2)

Proof : (a-b)•(a2+ab+b2) =

a3+a2b+ab2-ba2-b2a-b3 =

a3+(a2b-ba2)+(ab2-b2a)-b3 =

a3+0+0+b3 =

a3+b3

Check : 6 is not a cube !!

Ruling : Binomial can not be factored as the difference of two perfect cubes

Final result :

6x3 - 89y2

User Reino
by
3.4k points