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 37 Page 190

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

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.

Identifying the Slope and y-intercept

Since the given equation is not in slope-intercept form, let's rewrite it so that it will be easier to identify the slope and y-intercept.
- 1/2x+1/8y=3/4
- 1/2x+1/8y+1/2x=3/4+1/2x
Rewrite
1/8y=3/4+1/2x
y/8=3/4+1/2x
y/88 =(3/4+1/2x)8
y=(3/4+1/2x)8
y =3* 8/4+1* 8/2x
y =24/4+8/2x
y=6+4x
y=4x+6
Below we have highlighted the slope m and y-intercept b. y= 4x+ 6 The slope is 4. The y-intercept is 6, so the graph crosses the y-axis at the point (0, 6).

Graphing the Equation

A slope of 4 means that for every 1 unit we move in the positive horizontal direction, we move 4 units in the positive vertical direction. m= 4/1 ⇔ rise/run=4/1 To graph the equation, plot the y-intercept and then use the slope to find another point on the line.