1. Solving Equations Graphically
Section 2.1
Pre-Calculus AB Pre-AP/Dual, Revised ©2014
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2.1: Solving Equations Graphically

2. 2.1: Solving Equations Graphically
Key Terms
Solution is an equation of a number that produces a statement
Zero is an input of where the graph function crosses the x-axis
Intersection is where two graphs meet (DOES NOT HIT THE X-AXIS)
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2.1: Solving Equations Graphically

3. 2.1: Solving Equations Graphically
Intersection Method
Plug in the one side of the equation into Y1 and the other equation into Y2 = 0.
Press [2nd], TRACE, [5] or INTERSECT.
The calculator asks you 2 questions: FIRST CURVE and SECOND CURVE.
Then it says, “GUESS”. Arrow to an answer you want then press [ENTER].
Write answer as a SOLUTION SET.
Think of this: [2nd] [TRACE] [5] [ENTER] [ENTER] [ENTER]
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2.1: Solving Equations Graphically

4. 2.1: Solving Equations Graphically
Example 1
Solve f(x) = –2x3 + 3x2 = –3
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2.1: Solving Equations Graphically

5. 2.1: Solving Equations Graphically
Example 2
Solve x3 + 9 = 3x2 + 6x
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2.1: Solving Equations Graphically

6. 2.1: Solving Equations Graphically
Your Turn
Solve f(x) = x4 – 3x3 + 2x2 –1
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2.1: Solving Equations Graphically

7. 2.1: Solving Equations Graphically
Example 3
Solve |x2 – 4x – 3| = x3 + x – 6
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2.1: Solving Equations Graphically

8. 2.1: Solving Equations Graphically
Your Turn
Solve |x3 + 2| = –x2 + x + 5
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2.1: Solving Equations Graphically

9. 2.1: Solving Equations Graphically
Example 3
Solve |x2 – 4x – 3| = x3 + x – 6
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2.1: Solving Equations Graphically

10. 2.1: Solving Equations Graphically
Example 4
Solve 𝒙 𝟒 +𝟐 𝒙 𝟐 −𝟐𝒙−𝟏 =𝟎
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2.1: Solving Equations Graphically

11. 2.1: Solving Equations Graphically
Example 5
Solve 𝒙 𝟐 −𝟏 − 𝒙+𝟗 =𝟎
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2.1: Solving Equations Graphically

12. 2.1: Solving Equations Graphically
Example 6
Solve 𝟐𝒙 𝟐 −𝒙−𝟑 𝟖𝒙 𝟐 −𝟕𝒙−𝟒 =𝟎
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2.1: Solving Equations Graphically

13. 2.1: Solving Equations Graphically
Your Turn
Solve 𝟑𝒙 𝟓 −𝟏𝟓𝒙+𝟓 𝒙 𝟕 −𝟖 𝒙 𝟓 +𝟐 𝒙 𝟐 −𝟓 =𝟎
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2.1: Solving Equations Graphically

14. 2.1: Solving Equations Graphically
Assignment
Page EOO, 31
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2.1: Solving Equations Graphically