Download presentation

Presentation is loading. Please wait.

Published byJoshua Mills Modified over 3 years ago

1
EXAMPLE 1 Solve a quadratic equation having two solutions Solve x 2 – 2x = 3 by graphing. STEP 1 Write the equation in standard form. Write original equation. x 2 – 2x = 3 Subtract 3 from each side. x 2 – 2x – 3 = 0 STEP 2 Graph the function y = x 2 – 2x – 3. The x- intercepts are – 1 and 3. SOLUTION

2
EXAMPLE 1 ANSWER The solutions of the equation x 2 – 2x = 3 are – 1 and 3. Solve a quadratic equation having two solutions You can check – 1 and 3 in the original equation. x 2 – 2x = 3 (–1) 2 –2(–1) 3 = ? (3) 2 –2(3) 3 = ? 3 = 3 Write original equation. Substitute for x. Simplify. Each solution checks. CHECK

3
EXAMPLE 2 Solve a quadratic equation having one solution Solve – x 2 + 2x = 1 by graphing. SOLUTION STEP 1 Write the equation in standard form. Write original equation. – x 2 + 2x = 1 Subtract 1 from each side. – x 2 + 2x – 1 = 0

4
EXAMPLE 2 Solve a quadratic equation having one solution STEP 2 Graph the function y = – x 2 + 2x – 1. The x- intercept is 1. ANSWERThe solution of the equation – x 2 + 2x = 1 is 1.

5
EXAMPLE 3 Solve a quadratic equation having no solution Solve x 2 + 7 = 4x by graphing. SOLUTION STEP 1 Write the equation in standard form. Write original equation. x 2 + 7 = 4x Subtract 4x from each side. x 2 – 4x + 7 = 0

6
EXAMPLE 3 Solve a quadratic equation having no solution STEP 2 Graph the function y = x 2 – 4x + 7. The graph has no x -intercepts. ANSWER The equation x 2 + 7 = 4x has no solution.

7
GUIDED PRACTICE for Examples 1, 2 and 3 Solve the equation by graphing. 1. x 2 – 6x + 8 = 0 ANSWER 2, 4 2. x 2 + x = – 1 ANSWER no solution 3. – x 2 + 6x = 9 ANSWER 3

Similar presentations

© 2019 SlidePlayer.com Inc.

All rights reserved.

To make this website work, we log user data and share it with processors. To use this website, you must agree to our Privacy Policy, including cookie policy.

Ads by Google