GRE

$$\frac{1}{x}$$

$$\frac{1}{y}$$

a+1

$$\frac{1}{a}$$ - 1

|1-x|

1

The number of points with equal distance from three lines

3

The perimeter of the triangle

15

The sum of any two interior angles in Δ ABC

The sum of any two interior angles in Δ PQR

a

b

x

90

25000 +道题目

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