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Find an equation for the line with the given properties. Express your answer using either the general form or the slope-intercept form of the equation of a line. slope=-1/2, contain the point (3,-3)

User Georgian
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1 Answer

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Step 1. We are given the slope of the line. We will call this slope 'm':


m=-(1)/(2)

We also have the point (3, -3) which we will label as (x1,y1):


\begin{gathered} x_1=3 \\ y_1=-3 \end{gathered}

Required: Find the equation for the line.

Step 2. Since we have the slope and a point, we use the point-slope equation:


y-y_1=m(x_-x_1)

Substituting the known values:


y-(-3)=-(1)/(2)(x-3)

We will express our answer in the slope-intercept form:


y=mx+b

where m is the slope and b is the y-intercept.

Step 3. To convert our equation into the slope-intercept form, we need to simplify the operations:


\begin{gathered} y-(-3)=-(1)/(2)(x-3) \\ \downarrow \\ y+3=-(1)/(2)x+(3)/(2) \end{gathered}

Subtract 3 from both sides:


\begin{gathered} y=-(1)/(2)x+(3)/(2)-3 \\ \downarrow \\ \boxed{y=-(1)/(2)x-(3)/(2)} \end{gathered}

That is the equation in the slope-intercept form.

Answer:


\boxed{y=-(1)/(2)x-(3)/(2)}

User Nguyen Kien
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