Math Problem Statement

Find the x-intercepts of the graph of the function y = -x^2 + 5x + 2.

Solution

To find the xx-intercepts of the function y=x2+5x+2y = -x^2 + 5x + 2, we set y=0y = 0 and solve for xx:

0=x2+5x+20 = -x^2 + 5x + 2

This is a quadratic equation in the form ax2+bx+c=0ax^2 + bx + c = 0, with:

  • a=1a = -1
  • b=5b = 5
  • c=2c = 2

We use the quadratic formula to solve for xx: x=b±b24ac2ax = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}

Step 1: Substitute the values of aa, bb, and cc into the formula.

x=5±(5)24(1)(2)2(1)x = \frac{-5 \pm \sqrt{(5)^2 - 4(-1)(2)}}{2(-1)}

Step 2: Simplify inside the square root.

x=5±25+82x = \frac{-5 \pm \sqrt{25 + 8}}{-2} x=5±332x = \frac{-5 \pm \sqrt{33}}{-2}

Step 3: Simplify the expression further by factoring out the negative sign.

x=5±332x = \frac{5 \pm \sqrt{33}}{2}

So, the xx-intercepts are: x=5±332x = \frac{5 \pm \sqrt{33}}{2}

Answer

The correct answer is:

  • Option D: x=5±332x = \frac{5 \pm \sqrt{33}}{2}

Would you like more details on the solution process or have further questions?


Related Questions:

  1. How do we determine the vertex of a quadratic function?
  2. What is the significance of the discriminant in solving quadratic equations?
  3. Can a quadratic function have complex xx-intercepts?
  4. How do transformations affect the graph of a quadratic function?
  5. How does the value of aa in ax2+bx+cax^2 + bx + c affect the direction of the parabola?

Quick Tip:

In the quadratic formula, if b24ac>0b^2 - 4ac > 0, there are two real solutions; if it equals 0, there's one real solution; if it's less than 0, the solutions are complex.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Algebra
Quadratic Equations
Graphing

Formulas

Quadratic formula: x = (-b ± √(b² - 4ac)) / 2a

Theorems

Quadratic formula

Suitable Grade Level

Grades 9-11