9n²-49n² ????

Question

What would be the answer here? Please show the full solution... thank you ~

Answer 1

Shella, you indicated "factoring,” so let’s do that:

The expression (note: not equation),   9n^2  - 49n^2,  fits one of the very common forms that you should be learning:   x^2 – y^2    can be factored into  (x + y)(x – y)     [be sure to multiply this out to check it]

The terms here are squares  9n^2 is   (3n)^2   and 49n^2 is  (7n)^2

       So the expression factors into  (3n + 7n)(3n – 7n)     [answer, if you are asked just to factor]

             Note: we’ve done “factoring” as you mentioned, but the result may be reduced to   -40n^2

             Also note, we could have factored the expression to produce:  n^2(9 – 49)

                     [to make factoring expressions easier, factor out the GCF -- greatest common factor -- first)

Answer 2

There is no "answer." A solution is a value for the variable that makes the equation true. No equation is given. No solution can be determined. To get a appropriate answer you must use correct vocabulary. The topic listed is "factoring." And appropriate question would be: "How do you factor this binomial?"

 

9n² - 49n²            Simplifying using subtraction

-40n²

 

9n² - 49n²         Factoring  - not a direct approach

(3n)² - (7n)²

(3n + 7n)(3n - 7n)

(10n)(-40n)

-40n² 

 

n²(9 - 40)

n²(-40)

-40n²

Answer 3

9n^2-49n^2=n^2(9-49)=n^2(-40)=-40n^2