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    (Original post by Hydeman)
    Hmm. I may have misled you on this one. D: I'm thinking it's just s = (a + b + c)/2 as in the first question, even though that makes little sense... For the second equation, you've got that capital A as well which is more or less impossible to get rid of so I'd think it's just the simple answer from part I.
    so for part b do i not get integers??
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    For part c you need to notice something about the triangle with sides 6,8 and 10.
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    (Original post by User23)
    so for part b do i not get integers??
    No, it would be algebraic. The questions quite clear about that. I was wrong about it having to do with the area equation. It's just s = (a + b + c)/2 as far as I can see, unbelievable as it is.
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    (Original post by Hydeman)
    No, it would be algebraic. The questions quite clear about that. I was wrong about it having to do with the area equation. It's just s = (a + b + c)/2 as far as I can see, unbelievable as it is.
    The answers to part b are numbers. One of them is an integer.
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    (Original post by Hydeman)
    No, it would be algebraic. The questions quite clear about that. I was wrong about it having to do with the area equation. It's just s = (a + b + c)/2 as far as I can see, unbelievable as it is.
    are you sure it's algebraic?? because for the first triangle i got 7.4833 and the second triangle is pythagorean triples and as you can see for part c it asks for a simpler method which is b x h/2
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    (Original post by Hydeman)
    No, I'm thinking that's wrong because it includes area, which isn't in the question. I think it's just the simple s = (a + b + c)/2 from earlier although I've no idea why it's repeated. The first question does say calculate but mentions a hypothetical triangle with sides a, b and c so I don't see how you could give a different answer for that...

    Is there a markscheme for this anywhere? It shouldn't really be taking this long if it's for 13-year-olds so I'm going to assume that the long way is wrong... (by the way I don't think (s - a) factorises to s(1 -a); it would factorise to s(1 - a/s), which expands back to (s - a)).

    Sorry guys.
    I done this in my head lol. I realised I was wrong after and just stopped. I'll do this when I'm free.


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    (Original post by BuryMathsTutor)
    The answers to part b are numbers. One of them is an integer.
    Damn I read it wrong. Ignore me, OP. :getmecoat: It's integers. I was still thinking about the formula question.

    (Original post by User23)
    so for part b do i not get integers??
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    (Original post by User23)
    are you sure it's algebraic?? because for the first triangle i got 7.4833 and the second triangle is pythagorean triples and as you can see for part c it asks for a simpler method which is b x h/2
    Yeah, sorry about that. I was still thinking about the formula question. It's not algebraic, it's numbers because you have to use Heron's formula on the two triangles shown.
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    (Original post by Hydeman)
    Yeah, sorry about that. I was still thinking about the formula question. It's not algebraic, it's numbers because you have to use Heron's formula on the two triangles shown.
    oh thank god for that haha, i nearly had a heart attack
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    (Original post by Chittesh14)
    Hey, I really like your solution.
    But, I don't get how did you do 13/2 = 6.5 and make that one of the sides of the right-angled triangle.
    I get how you did 13 cm as the side opposite the right angle is the hypotenuse and then you used pythagoras.
    But, you done 13/2 = 6.5? Can you please explain
    basically I divided 13 by 2 to get the length from X to y (or y to z), because the trapeziums are identical, so X to y and y to z should be equal.
    the fact that I got 6.5 after doing pythagoras a second time to find the length of the left hand side of the trapezium is simply a coincidence.
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    (Original post by User23)
    thanks so much
    I need to go work on something now so I'll leave the answers for when you need them. Don't peek!

    Spoiler:
    Show
    b) Triangle 1: s = (6 + 5 + 3)/2 = 7
    Area = [7(7 - 6)(7 - 5)(7 - 3)]1/2 = 7.48 square units (2 dp)

    Triangle 2: s = (6 + 8 + 10)/2 = 12
    Area = [12(12 - 6)(12 - 10)(12 - 8)]1/2 = 24 square units

    c) Triangle 2 is a 3-4-5 triangle (easy to see if you divide each side by two) and is therefore right-angled. Simpler method would involve using (base x height)/2 = area. Check: (6 x 8)/2 = 24 square units. Matches answer from part b) therefore correct.

    d) Taking too long. :/ Sorry, you'll have to ask somebody else.
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    (Original post by Hydeman)
    I need to go work on something now so I'll leave the answers for when you need them. Don't peek!
    Spoiler:
    Show
    b) Triangle 1: s = (6 + 5 + 3)/2 = 7
    Area = [7(7 - 6)(7 - 5)(7 - 3)]1/2 = 7.48 square units (2 dp)

    Triangle 2: s = (6 + 8 + 10)/2 = 12
    Area = [12(12 - 6)(12 - 10)(12 - 8)]1/2 = 24 square units

    c) Triangle 2 is a 3-4-5 triangle (easy to see if you divide each side by two) and is therefore right-angled. Simpler method would involve using (base x height)/2 = area. Check: (6 x 8)/2 = 24 square units. Matches answer from part b) therefore correct.

    d) Taking too long. :/ Sorry, you'll have to ask somebody else.
    i did d on my own!!
 
 
 
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