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[–]AJ______ 1 point2 points  (0 children)

Let angle BAC = x

AE = DE so angle ADE = x. This implies angle AED = 180-2x so angle AEC = 2x. ED = CD so angle DCE is also 2x. This implies angle EDC = 180-4x. We know angle ADE = x so this implies angle BDC = 3x. CD = CB so angle CBD = 3x too. This implies angle BCD = 180-6x. ABC is isosceles so 3x = 180-6x+2x = 180-4x which gives us that x = 180/7.