8th grade math question.?

I have no idea where to start on this or even the slightest bit of knowledge of how to solve it...

So here it is, hopefully you guys can give tips.

"Choose the slope-intercept equation of the line that passes through the point (-2, 2) and is parallel to y = 4x + 7

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  • 8 years ago
    Favorite Answer

    y = 4x + 7 has slope 4.

    so, we require the equation of a line with slope 4 and passing through (-2,2)

    => y - 2 = 4(x + 2)

    i.e. y = 4x + 10

    :)>

  • Ian H
    Lv 7
    8 years ago

    Understandable if you missed class because you were ill, but if you were there and the teacher explained this topic and you "have no idea where to start on this or even the slightest bit of knowledge..." this might suggest you are not concentrating enough in maths. Some people "push" maths away from them, but it is important to realise early on that nearly every job regards English and Maths as basic requirements, and jobs help you get money fun and happiness, so consider trying harder from today.

    1) What is the slope-intercept equation of the line? It is

    y = mx + c

    m is the slope

    c is the position on the y-axis where the straight line crosses it, called the y intercept.

    Remember this, because this idea is used a lot.

    2) If you did a sketch of two lines that were parallel they would have the same slope.

    What is the slope of the line who's equation is below ?

    y = 4x + 7 to find the answer compare it with

    y = mx + c and remember that m is the slope.

    The slope of that line is 4; can you see that ?

    So a line that is parallel to that line must have its slope m = 4. That means it must be like

    y = 4x + c

    We still need to find out what c is, and we are helped because we are given the point (-2, 2)

    which is on the line. Substituting y = 2 when x = -2 yields

    2 = 4*(-2) + c

    so, c = 2 + 8 = 10 Now we know

    y = 4x + 10

    Please make sure you understand all this before copying.

    Regards - Ian

  • 8 years ago

    y = 4x + 7 has slope 4

    As the other line is parallel so its gradient/slope will also be 4.

    So the equation of a line with slope 4 and passing through (-2,2) will be

    y - 2 = 4(x + 2)

    y = 4x + 8 + 2

    y = 4x + 10

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