Pearson Algebra 2 Common Core, 2011
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Pearson Algebra 2 Common Core, 2011 View details
5. Using Linear Models
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Exercise 28 Page 98

We are given a point and a slope, so we can use the point-slope form.

x+y=0

Practice makes perfect
Equations in standard form are written in a specific format. Ax+ By= C In this form, A, B, and C are integers and A and B cannot both be zero. In this case, we haven't been given an equation, so we will need to use the given point and slope to write one.

Writing an Equation

The quickest way to write an equation, with a given point and a slope, is by using the point-slope form. An equation in point-slope form follows a specific format. y- y_1= m(x- x_1) In this form, m is the slope and the point ( x_1, y_1) lies on the graph of the line. Using the point ( -3, 3) as our point and the slope -1, we have everything needed to form a point-slope form equation. y- 3= -1(x-( -3)) ⇔ y-3=-(x+3) Note that there are infinitely many correct ways to write this equation in point-slope form, as long as we use a point that lies on the line.

Rearranging to Standard Form

We will use the Properties of Equality to rewrite the given equation in standard form.
y-3=-(x+3)
y-3=- x - 3
y=- x
x+y=0
Let's compare this result with the general standard form equation. Ax+ By&= C 1x+ 1y&= 0