Big Ideas Math Integrated I, 2016
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Big Ideas Math Integrated I, 2016 View details
2. Writing Equations in Point-Slope Form
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Exercise 39 Page 176

Consider the horizontal and vertical translations.

See solution.

Practice makes perfect
Let's begin by sketching their graphs. The first graph has a slope of 2 and a y-intercept of 0. To draw the second graph, we will write it in slope-intercept form.
y-1=2(x+3)
y-1=2x+6
y=2x+7
The second graph also has a slope of 2 but a y-intercept of 7. Let's graph this stuff!
If we recall the chapter on transformations, we know that: Horizontal Translation:& f(x-h) Vertical Translation:& f(x)+k By rewriting the general point-slope form, we can relate it to these types of transformations. y-k=m(x-h) ⇔ y=m(x-h)+k We see that point-slope form represents a horizontal translation by h and a vertical translation by k of the function y=mx. Let's substitute k=1 and h=- 3 into this general equation and simplify
y=m(x-h)+k
y=m(x-( - 3))+ 1
y=m(x+3)+1
This means y-1=2(x+3) is a translation of 3 units to the left and 1 unit up of the function y=2x. Let's show this below.