Question

Simplify this expression.

3x^2(7x^2 - 9)

Answer 1

3x^2 * 7x^2 + 3x^2*-9

Answer 2

3x2(7x2-9)

Final result :

3x2 • (7x2 - 9)
Reformatting the input :

Changes made to your input should not affect the solution:

(1): "x2" was replaced by "x^2". 1 more similar replacement(s).

Step by step solution :

Step 1 :

Raise x to the 2nd power
Exponentiation :

Equation at the end of step 1 :

(3 • (x2)) • ((7 • x2) - 9)
Step 2 :

Raise x to the 2nd power
Exponentiation :

Equation at the end of step 2 :

(3 • x2) • (7x2 - 9)
Step 3 :

Multiply 3x2 by 7x2-9
Trying to factor as a Difference of Squares :

3.1 Factoring: 7x2-9

Theory : A difference of two perfect squares, A2 - B2 can be factored into (A+B) • (A-B)

Proof : (A+B) • (A-B) =
A2 - AB + BA - B2 =
A2 - AB + AB - B2 =
A2 - B2

Note : AB = BA is the commutative property of multiplication.

Note : - AB + AB equals zero and is therefore eliminated from the expression.

Check : 7 is not a square !!

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

Final result :

3x2 • (7x2 - 9)

Answer 3

21x2 - 9



21x2 - 27x2



21x4 - 9



21x4 - 27

Answer 4

welsha will you go to my question i taged you in

Answer 5

that is the answer options

Answer 6

https://static.k12.com/calms_media/media/381000_381500/381291/2/87321e7650e21bc9de1df2e7f69d919d590fc743/53019_question.jpg