Question

For the quadratic equation −2x2−3x+2=0
, complete the table by testing each of the given values to determine whether it is a solution. Identify which one of the values is in the solution set. Only x =

is in the solution set.
Question 2
2. Solve x2=289
by inspection. There are two real solutions. Enter the lesser number first.

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Answers

GPT-4o mini
Let's start with the first part of your question regarding the quadratic equation \(-2x^2 - 3x + 2 = 0\).

To determine if a value is a solution of this equation, we can substitute the given values of \(x\) into the equation to see if the left side equals zero.

### Step 1: Solve for solutions using the quadratic formula

First, we can find the exact solutions to the quadratic equation using the quadratic formula:

\[
x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}
\]

In our case:
- \(a = -2\)
- \(b = -3\)
- \(c = 2\)

Calculating \(b^2 - 4ac\):

\[
b^2 - 4ac = (-3)^2 - 4(-2)(2) = 9 + 16 = 25
\]

Now, substituting into the quadratic formula:

\[
x = \frac{-(-3) \pm \sqrt{25}}{2(-2)} = \frac{3 \pm 5}{-4}
\]

Calculating the two possible solutions:

1. \(x = \frac{3 + 5}{-4} = \frac{8}{-4} = -2\)
2. \(x = \frac{3 - 5}{-4} = \frac{-2}{-4} = \frac{1}{2}\)

Thus, the solutions to the equation are \(x = -2\) and \(x = \frac{1}{2}\).

### Step 2: Testing the Values

To complete the table, let's test some specific values (let's say you have \(x = -2\) and \(x = \frac{1}{2}\) and additional values, e.g., \(0, 1, -3\), or any others). You would substitute each of those into \(-2x^2 - 3x + 2\) and evaluate.

For example:

1. **For \(x = -2\)**:
\[
-2(-2)^2 - 3(-2) + 2 = -2(4) + 6 + 2 = -8 + 6 + 2 = 0
\]
(Solution)

2. **For \(x = \frac{1}{2}\)**:
\[
-2\left(\frac{1}{2}\right)^2 - 3\left(\frac{1}{2}\right) + 2 = -2\left(\frac{1}{4}\right) - \frac{3}{2} + 2 = -\frac{1}{2} - \frac{3}{2} + 2 = -2 + 2 = 0
\]
(Solution)

3. **For \(x = 0\)**:
\[
-2(0)^2 - 3(0) + 2 = 0 + 0 + 2 = 2
\]
(Not a solution)

4. **For \(x = 1\)**:
\[
-2(1)^2 - 3(1) + 2 = -2 - 3 + 2 = -3
\]
(Not a solution)

5. **For \(x = -3\)**:
\[
-2(-3)^2 - 3(-3) + 2 = -2(9) + 9 + 2 = -18 + 9 + 2 = -7
\]
(Not a solution)

Given the evaluations above, the values \(x = -2\) and \(x = \frac{1}{2}\) are indeed in the solution set.

### Answer for Question 1:

Only \(x = -2\) and \(x = \frac{1}{2}\) are in the solution set.

---

### Question 2: Solve \(x^2 = 289\) by inspection

To solve \(x^2 = 289\), we can take the square root of both sides.

\[
x = \pm \sqrt{289}
\]

Calculating \(\sqrt{289}\):

\[
\sqrt{289} = 17
\]

Thus, the two solutions are:

\[
x = 17 \quad \text{and} \quad x = -17
\]

### Final Answer for Question 2:

\[
\{ -17, 17 \}
\]

---

So your complete answers would be:

**Question 1:** Only \(x = -2\) and \(x = \frac{1}{2}\) are in the solution set.
**Question 2:** \(\{-17, 17\}\).

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