Writing Linear EquationsWriting Linear EquationsWriting Linear EquationsWriting Linear Equations GIVEN A GRAPH

! Step 1: Identify the ___________ and ____-_______________

! Step 2: Write the equation in slope-intercept form: ___________________

Some ExamplesSome ExamplesSome ExamplesSome Examples…

m = _________ b = _________ Equation: __________________

m = _________ b = _________ Equation: __________________

1 2

3 4

5 6

Equation: __________________ Equation: __________________

Equation: __________________ Equation: __________________

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x

y

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x

y

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x

y

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Unit 6 Day 4 Notes

slope y intercept

y = mx + b

Main Ideas/Questions Notes

The The The The PointPointPointPoint----Slope Slope Slope Slope FormulaFormulaFormulaFormula

Used to write the equation of a line when given a point (x1, y1) and the slope of the line (m)

Formula:

*Be sure to distribute and solve for y!

Examples!Examples!Examples!Examples!

Find the equation of the line given

the point and slope.

1. (4, 1); slope = 2 2. (2, 4); slope = 21

3. (-6, 0); slope = 32 4. (-8, -1); slope =

43

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5. (4, -3); slope = -1

6. (0, -9); slope = 4

Name:

Topic:

Class:

Date:

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Unit 6 Day 4 Notes Cont.

Given a point & slope

What if you What if you What if you What if you are given are given are given are given

Two PTwo PTwo PTwo Points?oints?oints?oints?

To write a linear equation given two points,

(x1, y1) and (x2, y2), follow this process:

Use the Slope Formula Use the Point-Slope Formula

Examples!Examples!Examples!Examples!

Find the equation of

the line given the two points.

7. (-3, 7) and (1, -1) 8. (-6, -7) and (3, -4)

9. (2, -1) and (4, -6) 10. (-3, -8) and (2, 7)

11. (-6, -3) and (-4, -1) 12. (-4, 7) and (6, 2)

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Unit 6 Day 4 Notes Cont. Given two points