Introduction to Functions: Background You’ll Need 3

  • Recognize positive, negative, and zero slope

sign of slope

The sign of a slope tells us the direction a line moves:

  • Positive slope: Line rises from left to right
  • Negative slope: Line falls from left to right
  • Zero slope: Line is horizontal
  • Undefined slope: Line is vertical

The image shows four arrows. The first arrow is slanted and pointing up and to the right and is labeled “positive”. The second arrow is slanted and pointing down and to the right and labeled “negative”. The third arrow is horizontal and labeled “zero”. The fourth arrow is vertical and labeled “undefined”.

For lines given in the form [latex]y=mx+b[/latex], slope is [latex]m[/latex], the coefficient of [latex]x[/latex].
Identify the type of slope for each scenario:a)This figure shows the graph of a straight line on the x y-coordinate plane. The x-axis runs from negative 8 to 8. The y-axis runs from negative 8 to 8. The line goes through the points (0, negative 2) and (3, 3).b)This figure shows the graph of a straight line on the x y-coordinate plane. The x-axis runs from negative 8 to 8. The y-axis runs from negative 8 to 8. The line goes through the points (0, 2) and (3, 1).

c) [latex]y=-7x+3[/latex]

d) [latex]y = -2[/latex]