Big Ideas Math: Modeling Real Life, Grade 8
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Big Ideas Math: Modeling Real Life, Grade 8 View details
Chapter Review
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Exercise 27 Page 189

What information can you learn from the slope-intercept form of an equation?

Graph:

x-intercept: 3

Practice makes perfect
Equations written in slope-intercept form follow a specific format. y= mx+ b In this form, m represents the slope of the line and b represents the y-intercept. Below we have highlighted the slope m and y-intercept b.

y= 2x - 6 ⇔ y= 2x+( - 6) The slope is 2. The y-intercept is - 6, so the graph crosses the y-axis at the point (0, - 6).

Graphing the Equation

A slope of 2 means that for every 1 unit we move in the positive horizontal direction, we move 2 units in the positive vertical direction. m= 2/1 ⇔ rise/run=2/1 To graph the equation, plot the y-intercept and then use the slope to find another point on the line.

As we can see, the x-intercept is 3. This means that the graph crosses the x-axis at the point ( 3,0).