Gwen was asked to solve 3x2−20=7

by factoring using the difference of squares pattern. What is/are the correct solution(s)?(1 point)
Responses

x=−3
, x=3
x equals negative 3 , x equals 3

x=9
, x=−9
x equals 9 , x equals negative 9

x=3
x equals 3

x=−3
x equals negative 3

1 answer

To solve the equation \(3x^2 - 20 = 7\) by factoring using the difference of squares pattern, we first need to set the equation to zero:

\[3x^2 - 20 - 7 = 0\]

This simplifies to:

\[3x^2 - 27 = 0\]

Next, we can factor out the common factor of 3:

\[3(x^2 - 9) = 0\]

Now we recognize that \(x^2 - 9\) is a difference of squares, which can be factored further:

\[3(x - 3)(x + 3) = 0\]

Setting each factor equal to zero gives us:

  1. \(x - 3 = 0\) → \(x = 3\)
  2. \(x + 3 = 0\) → \(x = -3\)

Thus, the solutions to the equation \(3x^2 - 20 = 7\) are:

\[x = 3 \quad \text{and} \quad x = -3\]

So the correct response is:

x = −3, x = 3 (x equals negative 3, x equals 3).