In the figure at right, it is given than BDC is straight, BD = DA, and AB = AC = DC. Find the size of angle C

Question

anonymous · Answer

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asnaseer · Answer

do you know what an isosceles triangle is and what its properties are?

anonymous · Answer

Yeah. I figured angles B and DAB must be equal, angles CDA and CAD must be equal, and angles B and C must be equal

asnaseer · Answer

you are almost there - now assign a symbol to angle ABD - lets call it x, and fill-in all the other angles you know using this symbol, e.g. from what you have already said we get:
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now find y in terms of x and then use the property of the sum of the angles in a triangle to solve for x.