Question

In quadrilateral ABCD, AC = x +9 and BD = 2x-11 For what value of x is ABCD a rectangle?

Answer 1

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Answer:

20

Explanation:

The figure will be a rectangle when the diagonals AC and BD are the same length:

AC = BD

x +9 = 2x -11

20 = x . . . . . . . add 11-x to both sides

ABCD will be a rectangle when x=20.