find the value of x in this equation: f(x) = x^2 - 2x + 7 when f(x) = 10

1 answer

To find the value of \( x \) in the equation \( f(x) = x^2 - 2x + 7 \) when \( f(x) = 10 \), we can set up the equation:

\[ x^2 - 2x + 7 = 10 \]

Now, we can solve for \( x \):

  1. Subtract 10 from both sides:

\[ x^2 - 2x + 7 - 10 = 0 \]

This simplifies to:

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

  1. Now, we can factor the quadratic equation:

\[ (x - 3)(x + 1) = 0 \]

  1. Setting each factor to zero gives us the possible solutions for \( x \):

\[ x - 3 = 0 \quad \Rightarrow \quad x = 3 \] \[ x + 1 = 0 \quad \Rightarrow \quad x = -1 \]

Thus, the values of \( x \) that satisfy the equation \( f(x) = 10 \) are \( x = 3 \) and \( x = -1 \).