Question

find the equation of the line that passes through (4,8) with slope -3. write in slope intercept form

Answer 1

you have to put it in Point Slope Form.

ABOUT POINT SLOPE FORM:

• y- Y1 = m(x - X1)
• Y1 & X1 is a point on the line
• The form allows you to identify the slope & the point on the line

ABOUT PROBLEM:

• Since the slope is -3, it represents m in the Point Slope Form
• 4 represents X1
• 8 represents Y1

y - Y1 = m(x - X1)

y - 8 = -3(x - 4) --- IN Point Slope Form

If you want to put it in Slope Intercept Form, you can solve it:

y - 8 = -3(x - 4)

y - 8 = -3x + 12

  + 8          + 8

y = -3x + 20 --- IN Slope Intercept Form

• Remember, a negative times a negative becomes a positive