Question

Difference of squares: What is x^2-9=0? please help me....​

Answer 1

Answer:

3 or -3

Step-by-step explanation:

You need to factor it to be able to find the solution.

x^2-9=0

(x+3)(x-3)=0  You now need to find 'each' zero, because if one parenthesis equals 0, then you are multiplying the rest of the equation by 0 which will equal 0.

x+3=0  Subtract three

x= -3    

x-3=0  Add three

x= 3

x^2-9 will equal 0 when x is either +3 or -3

Answer 2

Answer:

x=3  x=-3

Step-by-step explanation:

x^2-9=0

We know this is the difference of squares

a^2 - b^2 = (a-b) (a+b)

(x-3)(x+3) =0

Using the zero product property

x-3 =0  x+3 =0

x=3  x=-3