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    This question was from one of the sample assessment materials from edexcel for the new maths 9-1 exams and im not sure how to answer it.

    I know that opposite angles are equal in a parallelogram and add up to 360 degrees
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    (Original post by JackT2000)
    This question was from one of the sample assessment materials from edexcel for the new maths 9-1 exams and im not sure how to answer it.

    I know that opposite angles are equal in a parallelogram and add up to 360 degrees
    Heres the question
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    Opposite angles are congruent, that is 5x-20 = 2x+43 and the sum of interior angles is 360 degrees.
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    (Original post by NotNotBatman)
    Opposite angles are congruent, that is 5x-20 = 2x+43 and the sum of interior angles is 360 degrees.
    5x - 20 = 2x + 43 (-2x)

    3x - 20 = 43 (+20)

    3x. = 63 (/3)

    x = 21
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    (Original post by JackT2000)
    5x - 20 = 2x + 43 (-2x)

    3x - 20 = 43 (+20)

    3x. = 63 (/3)

    x = 21
    Correct.
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    (Original post by NotNotBatman)
    Correct.
    Ok now how would I find the value of X and y for the other pair of opposite angles
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    (Original post by JackT2000)
    Ok now how would I find the value of X and y for the other pair of opposite angles
    There is only one value of x, x=21. Use the fact that the interior angle sum is 360 in a quadrilateral and substitute x=21.
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    (Original post by NotNotBatman)
    There is only one value of x, x=21. Use the fact that the interior angle sum is 360 in a quadrilateral and substitute x=21.
    There is a missing angle though ?
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    now that you know x you can work out 2 angles exactly. the other 2 are equal to each other, and the total of the 4 angles is 360 degrees.
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    (Original post by JackT2000)
    There is a missing angle though ?
    diagonally opposite angles are equal.
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    (Original post by the bear)
    now that you know x you can work out 2 angles exactly. the other 2 are equal to each other, and the total of the 4 angles is 360 degrees.
    5(21) - 20 = 85
    2(21) + 43 = 85

    Now what do I do ?
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    (Original post by JackT2000)
    5(21) - 20 = 85
    2(21) + 43 = 85

    Now what do I do ?
    consider the total of the angles in a Quadrilateral
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    (Original post by the bear)
    consider the total of the angles in a Quadrilateral
    I don't understand
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    the 4 angles add up to 360 degrees.
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    (Original post by the bear)
    the 4 angles add up to 360 degrees.
    Yeah I know that but there is a missing angle and I don't know what it is?

    Could you show me the full workings for this question please?
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    (Original post by JackT2000)
    Yeah I know that but there is a missing angle and I don't know what it is?

    Could you show me the full workings for this question please?
    Sadly this is forbidden. We can only give hints along the way ?

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    (Original post by JackT2000)
    Yeah I know that but there is a missing angle and I don't know what it is?

    Could you show me the full workings for this question please?
    you said so yourself, opposite angles are equal. therefore if there is a missing angle, take a look at the opposite angle, and it will be the same!
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    85 + 85 + ? + ? = 360
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    (Original post by dnr_23)
    you said so yourself, opposite angles are equal. therefore if there is a missing angle, take a look at the opposite angle, and it will be the same!
    So 4y - 5x = 4y - 5x
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    360-85-85 = 190. Half of that is what the bottom right is equal to. Half of 190 = 95. You know what x is. Solve for y.
 
 
 
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