Questions: Use factoring to solve the quadratic equation. Check by substitution or by using a graphing utility and identifying (x)-intercepts.
[ x^2-x-72=0 ]
The solution set is (square)
Transcript text: Use factoring to solve the quadratic equation. Check by substitution or by using a graphing utility and identifying $x$-intercepts.
\[
x^{2}-x-72=0
\]
The solution set is $\square$
Solution
Solution Steps
Step 1: Identify the Quadratic Equation
The given quadratic equation is \( x^2 + (-1)x + (-72) = 0 \).
Step 2: Factor the Quadratic Equation
To factor the equation, we find two numbers \(m\) and \(n\) such that \(m + n = -1\) and \(m \cdot n = -72\).
After calculation, we find that \(m = 9\) and \(n = -8\),
so the factored form of the equation is \((x - 9)(x + 8) = 0\).
Step 3: Solve for \(x\)
Setting each factor equal to zero gives us the solutions \(x = 9\) and \(x = -8\).
Step 4: Verification
To verify the solutions, substitute them back into the original equation or use a graphing utility.
If the solutions are correct, they will satisfy the original equation or correspond to the \(x\)-intercepts on the graph.
Final Answer:
The solutions to the quadratic equation \( x^2 + (-1)x + (-72) = 0 \) are \(x = 9\) and \(x = -8\).