To write the equation of a line in slope-intercept form (y=mx+b) given the slope (m) and y-intercept (b): 1) Identify the y-intercept as the y-value when x=0 2) Plug the slope (m) and y-intercept (b) into the slope-intercept equation 3) To write the equation when given two points, use the point-slope formula: y-y1=m(x-x1), where m is the slope calculated from the two points.

1. Equations of a LineHow do you write anEQUATION of a LINEinSLOPE INTERCEPT FORM?Y = m x + bm = slopeb = y-intercept

2. Vocabulary RiseRunSlope Negative slopePositive slopeNo slopeUndefined slopey – interceptSlope-intercept formatPoint –slope formaty=mx+bOrdered Pair

3. How do you write the equation of a line when given the slope and the y-intercept?Y-intercept(0,4)m = 3y=mx+bsoy=3x+4

4. How do you write the equation of a line when given the slope and the y-intercept?Y-intercept(0,-3)m = -5y=mx+bsoy=-5x-3

5. How do you write the equation of a line when given the slope and the y-intercept?Y-intercept(0,-4)m =1y=mx+by=x-4so

6. How do we write the equation of this line?Y=x+1First:Identify the y-intercept(0,1)Second:Determine the slope by counting the RiseRunY-interceptRISE22m == 1RUN

7. How do we write the equation of this line?y=-5x-6First:Identify the y-interceptriseRISEm=runRUNSecond:Determine the slope by counting the RiseRun(0, -6)Y-inyercept

8. How do you write the equation of a line when given two points on the line?Given points: (4,5) and ( -2,3)Y=mx+bM=(4,5)5=1*4+b5=4+b5-4=4-4+b1=b(x2, y2)(x1, y1)Use point-slope format:

9. How do you write the equation of a line when given two points on the line?Given points: (-2,6) and ( 4,-6)Y=mx+bM=(4,-6)-2Y = m x + b-6 = -2 (4) + b-6 = -8 + b-6 + 8 = -8 + 8 + b 2 = b(x2, y2)(x1, y1)Use point-slope format: