Graphing and Writing Equations in Slope-Intercept Form Algebra 1 CC Graphing and Writing Equations in Slope-Intercept Form

The three forms of writing a linear equation that we will cover this week Slope-Intercept form Standard Form Point-Slope Form

Example 1 Write an equation of the line shown

Example 2 Write an equation of the line that passes through the points (4, -2) and (-2, 2)

Example 3 Write the equation of the line that passes through the point (-4, -9) and has a slope of 2.

Graphing a Linear Equation Step 1: Rewrite the equation in slope-intercept form (if necessary). Step 2: Identify the slope and y-intercept Step 3: Plot the y-intercept Step 4: Use the slope to plot a second point and then draw a line through the two points. It is optional, but highly recommended to draw more than two points to graph a linear equation

Example 4 & 5 Identify the slope and y-intercept of the line with the given equations and then graph the equations. 4) 5) 4x – 3y = 15

Example 6 Write an equation for the linear function f with the given values f(6) = -4, f(9) = -9

Two lines in the same plane are parallel if they do not intersect. Parallel lines have the same slope. Two lines in the same plane are perpendicular if they intersect to form a right angle. Perpendicular lines have slopes that are opposite reciprocals.

Example 7 Tell whether the following graphs are parallel, perpendicular, or neither. y = 2x + 4 4x + 2y = 12

Example 8 Tell whether the following graphs are parallel, perpendicular, or neither. 3x + 4y = 24 -4x + 3y = 20