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Math Help - Algebra 1 - Slope help

  1. #1
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    Algebra 1 - Slope help

    Yea im back more help needed

    Write an equation of the line shown in each graph, please explain how to do this one and i can understand the rest sorry its sideways i took the pic with my phone

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  2. #2
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    You're looking for a line with the formula y= mx+ b , in which m= slope and b= y intercept.


    First, use the slope formula with your two points to find the slope.
    \frac{y2-y1}{x2-x1}
    That is "m."

    Next, plug one of your points, such as (-5,0) into the equation.

    0= -5m + b
    You should have m already from the slope formula. You then solve for b.

    Finally, you put it all together.

    y= mx+ b

    Alternately, to find b you can use the formula y1-y= m(x-x1), called the point-slope formula.
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  3. #3
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    please explain more my head is just popping right now
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  4. #4
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    Your two points are (-5, 0) and (0, 2).

    You are looking for the equation of the line, i.e. y = mx + c where m is the slope and c is the y-intercept.

    We're given the y-intercept. It's 2.

    So we just need the slope.

    Here, x_1 = -5, y_1 = 0, x_2 = 0, y_2 = 2.

    So using the slope of a line formula

    y = \frac{y_2 - y_1}{x_2 - x_1} = \frac{2 - 0}{0 - -5} = \frac{2}{5}.

    So the equation of the line is

    y = \frac{2}{5}x + 2, or if you want to clean it up...

    5y - 2x - 10 = 0.
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