Writing the Equation of a Line

Review of Slope-Intercept Form The slope-intercept form of a linear equation is y = mx + b. m represents the slope b represents the y-intercept

Write the Equation in Slope-Intercept Form 5. The slope is 2; the y-intercept is 5 6. The slope is -4; the y-intercept is 0 7. The slope is - ; the y-intercept is -3 8. The slope is ; the y-intercept is y = 2x + 5 y = -4x y = - x – 3

Find the Equation of the Line Given the Slope and y-intercept Substitute m and b into y = mx + b m = -3, b = 1 m = -2, b = -4 m = 0, b = 10 m = 1, b = 0 m = 0, b = 0 y = -3x + 1 y = -2x - 4 y = 0x + 10, y = 10 y = 1x + 0, y = x y = 0x + 0, y = 0

Slope-intercept form of an equation Given the slope and y-intercept, write the equation of a line in slope-intercept form. 1) m = 3, b = -14 2) m = -½, b = 4 3) m = -3, b = -7 4) m = 1/2 , b = 0 5) m = 2, b = 4 Slope-intercept form of an equation Y = mx + b

Example 1 b = -3 m = y = x - 3 x y +2 +3

Example 2 b = 1 m = y = x + 1 x y +1 -2

Example 3 b = 4 m = 0/1= 0 y = 0x + 4, y = 4 x y

Write an Equation in Slope-Intercept Form 10. Write the Equation for this line Slope = m = y-intercept = b 2 = -2 3

Write an Equation in Slope-Intercept Form 11. Write the Equation for this line Slope = m = y-intercept = b 4 5 = 3

Write an Equation in Slope-Intercept Form 12. Write the Equation for this line Slope = m = y-intercept = b = -2 2 = 1 4