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How do I know that if line AB = AC, there'll be an isosceles? Watch

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    Part C is the one I don't understand.

    How am I supposed to take AC = AB? Does it mean that the gradients are the same (well, considering the answer, no, but still)? The lines are the same? What is the question implying? I know that the lines would form an isosceles, but how am I supposed to know that just out of nothing?
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    AC = AB just means the length of the lines are the same, not their gradients
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    I'm not sure if you've completed this or not, but here's some help anyway!

    From part b, you should have found that AB has length of root 41.
    You do part C in a similar way. So, you know A is (7,4) and C is (2,t).

    AC^2 = (t-4)^2 + (2-7)^2.

    And you are given that AC = AB. So, AC is also equal to root 41.
    So, ((root 41))^2 = (t-4)^2 + (2-7)^2.
    Can you expand this for me and see what you get t as being?

    Once you've done that, i'll help you with part d) if you need it.
 
 
 
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