Given the quadratic equation (2x−7)(x+9)

check the solution in the following table by substitution and evaluating

(1 point)
Value Substituted Evaluate: Step 1 Step 2: True or False Statement?
(2x−7)(x+9)=0
original question
0 (2(0)−7)((0+9)=0
(−7)(9)=0
−63=0
false
3
-9
9


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1 answer

To solve the quadratic equation \((2x - 7)(x + 9) = 0\) by substitution, we need to substitute the given values into the equation and evaluate whether the result is zero.

We will check the values \(0\), \(3\), \(-9\), and \(9\).

1. For \( x = 0 \):

Substitution: \[ (2(0) - 7)(0 + 9) = (0 - 7)(9) = (-7)(9) = -63 \] This means: \[ -63 \neq 0 \quad \text{(False)} \]

2. For \( x = 3 \):

Substitution: \[ (2(3) - 7)(3 + 9) = (6 - 7)(12) = (-1)(12) = -12 \] This means: \[ -12 \neq 0 \quad \text{(False)} \]

3. For \( x = -9 \):

Substitution: \[ (2(-9) - 7)(-9 + 9) = (-18 - 7)(0) = (-25)(0) = 0 \] This means: \[ 0 = 0 \quad \text{(True)} \]

4. For \( x = 9 \):

Substitution: \[ (2(9) - 7)(9 + 9) = (18 - 7)(18) = (11)(18) = 198 \] This means: \[ 198 \neq 0 \quad \text{(False)} \]

Summary of Results:

  • For \( x = 0 \): False
  • For \( x = 3 \): False
  • For \( x = -9 \): True
  • For \( x = 9 \): False

You can now fill in the table with the results. If you need further assistance, let me know!