In the diagram, mÐ ABC = 90° and arc AD = 78°. What is the measure of arc CD?
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△cde maps to △stu with the transformations (x, y) arrowright (x − 2, y − 2) arrowright (3x, 3y) arrowright (x, −y). if cd = a + 1, de = 2a − 1, st = 2b + 3 and tu = b + 6, find the values of a and b. the value of a is and the value of b is .

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How many solutions does the nonlinear system of equations graphed below have? a. one b. zero c. four d. two