$\"\"$

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The slope-intercept form of a line equation is $\"\"$ .

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Angle between two lines:

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If two non perpendicular lines have slopes $\"\"$ and $\"\"$ , the angle between

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the two lines is $\"\"$

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Line 1: $\"\"$

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Write the line equation in slope-intercept form.

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$\"\"$

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Compare the line equation $\"\"$ with $\"\"$ .

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The slope is $\"\"$

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Line 2: $\"\"$

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Write the equation in slope-intercept form.

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$\"\"$

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Compare the line equation $\"\"$ with $\"\"$ .

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The slope is $\"\"$ .

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$\"\"$

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The angle between the two lines is $\"\"$

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Substitute $\"\"$ and $\"\"$ in above equation.

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$\"\"$

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Conversion from degrees to radians:

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$\"\"$ radians.

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$\"\"$

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The angle between lines is $\"\"$ or $\"\"$ .

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$\"\"$

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The angle between lines is $\"\"$ or $\"\"$ .