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    Name:  maths.jpg
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Size:  13.7 KB Can anyone help me with what formula I use to anwser this question? ... confused! Thanks guys
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    make the equations equal to each other (i.e 36-(x-2)^2=20
    then set equal to 0, and solve as a quadratic
    one result will be 6, the other will be the one you are looking for. obvs the y coord will be 20
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    I would just take the equation of the curve, set y =20 and solve. You know that one solution is x=6, you're looking for the other one.

    Yikes. Edited and correct now.
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    (Original post by fawnbx)
    Can anyone help me with what formula I use to anwser this question? ... confused! Thanks guys
    No need to use any formula, just investigate it and use some logic.

    The parabola has a line of symmetry (can you figure out what it is?) and since R,S have the same y coordinate, then that means they are both reflections of each other in this line of symmetry. So, since you know S, you can figure out what R must be reflecting the x-coordinate of S in the line of symmetry.
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    (Original post by fawnbx)
    Name:  maths.jpg
Views: 16
Size:  13.7 KB Can anyone help me with what formula I use to anwser this question? ... confused! Thanks guys
    Since S and R have the same y co-ordinate, you can find the line of symmetry of the parabola, to work out the x co-ordinate of R.

    Look at the question. You have been given the completed square from of the parabola.

    In the quadratic a(x+p)^2+q, the co-ordinates of the vertex are (-p,q).
    So x = -p is your line of symmetry!

    Use this skeleton structure solution I have given you to solve it!
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    Aw Thank you guys!!
 
 
 
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