Using the Calculator to Solve Equations

Do Now: Explain what “solution” means in terms of an equation.

The numerical value of the variable that makes the mathematical sentence true.

How do we use the calculator to solve equations?

Solve x2 – 3x + 2 = 0

y1 = x2 – 3x + 2

y2 = 0

2nd TRACE (calc)

5:intersect

Enter, Enter

move cursor

Enter

x =

Repeat for other intersection point

x =

Steps

1. Enter left side of = into y1

2. Enter right side of = into y2

3. Hit

2nd TRACE(Calc)

5 (intersect)

Enter, enter

move cursor close to

intersection point

Enter

x value is solution

Practice

Check HW

2. z2 – 5z + 4 = 0

5. c2 + 6c + 5 = 0

8. y2 + 11y + 24 = 0

11. x2 + x – 6 = 0

14. x2 – x – 12 = 0

17. m2 – 64 = 0

20. s2 – s = 0

Steps

1. Enter left side of = into y1

2. Enter right side of = into y2

3. Hit

2nd TRACE(Calc)

5 (intersect)

Enter, enter

move cursor close to

intersection point

Enter

x value is solution

More Practice

1. y2 - 3y = 28

2. r2 = 4

3. x2 = 9x – 20

4. .

Steps

1. Enter left side of = into y1

2. Enter right side of = into y2

3. Hit

2nd TRACE(Calc)

5 (intersect)

Enter, enter

move cursor close to

intersection point

Enter

x value is solution

x

x 12

2

2