<h2>Answer:</h2><h3>
A. 
</h3><h2 />
Find the values a, b, and c to substitute into the quadratic formula.
<h2>Remember:</h2><h3>Standard form</h3>
Notice how there are a, b, and c. Everything is left of the equal sign, leaving 0 on the right.
<em>ax² + bx + c = 0</em>
<h3>Quadratic formula</h3>
Notice how there are a, b, and c too, just like in standard form. After we find standard form, we can substitute a, b and c values into the quadratic formula.

<h2>Step-by-step solution</h2>
Here are the steps we will follow:
- Rearrange the equation from the question into standard form.
- Determine the values for a, b, and c.
- Substitute a, b, and c into the quadratic formula.
- Compare options and simplify as needed.
<h3>Rearrange into standard form</h3>
Move everything to the left while keeping both sides equal.
x² + 1 = 2x – 3 Equation from the question
x² + 1 + 3 = 2x – 3 + 3 Add three to both sides.
x² + 1 + 3 = 2x -3 + 3 cancels out to 0.
x² + 4 = 2x Simplify.
x² + 4 – 2x = 2x – 2x Subtract 2x from both sides.
x² + 4 – 2x = 0 No numbers on the right side is the same as 0.
x² – 2x + 4 = 0 Rearrange to follow ax² + bx + c = 0.
<h3>Determine a, b, and c values</h3>
Find a, b, and c from standard form.
ax² + bx + c = 0 Standard form
x² – 2x + 4 = 0 No number attached to x² means a = 1.
a = 1, b = –2, and c = 4
<h3>Substitute into the quadratic formula</h3>
Substitute a = 1, b = –2, and c = 4 into the quadratic formula.
Here is how our formula set up should look:

<h3>Compare answer options</h3>
Let's compare formula set up to the options in the question.
The denominator is 2(1). So, the answer is <u>not option B</u>.
Inside the square root, it says –4(1)(4). So, the answer is <u>not option D</u>.
This leaves us with either option A or option C.
<h3>Simplify</h3>
Before the ±, it says –(–2). When simplified, –(–2) is 2.
Option C has –2. So, the answer is <u>not option C</u>.
Inside the square root, it says (–2)², which is equal to 2².
When solving exponents of negative numbers,
- an odd exponent results in a negative product, and;
- an even exponent results in a positive product.
The exponent 2 is even.
(–2)² = 4
∵ (–2)² = 4 and 2² = 4
∴ (–2)² = 2²
(–2)² is the same as 2².
Therefore, the answer is <u>option A</u>.