Factor the high-degree polynomial expression 7x2+42x+63=0

and then solve for the value of x
.(1 point)

1 answer

To factor the polynomial expression \(7x^2 + 42x + 63 = 0\), we can first factor out the greatest common factor (GCF) from the expression.

The GCF of \(7x^2\), \(42x\), and \(63\) is \(7\). Thus, we can factor out \(7\):

\[ 7(x^2 + 6x + 9) = 0 \]

Next, we need to factor the quadratic expression \(x^2 + 6x + 9\). This quadratic can be factored as follows:

\[ x^2 + 6x + 9 = (x + 3)(x + 3) = (x + 3)^2 \]

Putting it all together, the original expression factors to:

\[ 7(x + 3)^2 = 0 \]

To solve for \(x\), we set the factored equation equal to zero:

\[ 7(x + 3)^2 = 0 \]

Dividing both sides by \(7\):

\[ (x + 3)^2 = 0 \]

Taking the square root of both sides:

\[ x + 3 = 0 \]

Subtracting \(3\) from both sides gives:

\[ x = -3 \]

Thus, the solution for \(x\) is:

\[ \boxed{-3} \]