Big Ideas Math Integrated I, 2016
BI
Big Ideas Math Integrated I, 2016 View details
Chapter Review
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Exercise 17 Page 209

What do parallel lines have in common?

y=-4x+9

Practice makes perfect
Consider the given equation of a line. y= -4x+2 When lines are parallel, they have the same slope. Because of this, we know that all lines that are parallel to the line whose equation is given will have a slope of -4. We can write a general equation in slope-intercept form for these lines. y= -4x+ b We are asked to write the equation of a line parallel to the given equation that passes through the point ( 1, 5). By substituting this point into the above equation for x and y, we will be able to solve for the y-intercept b of the parallel line.
y=-4x+b
5=-4( 1)+b
â–Ľ
Solve for b
5=-4+b
9=b
b=9
Now that we have the y-intercept, we can write the parallel line to y=-4x+2 through (1,5). y= -4x+ 9