$A$ is the point $(1, 2)$ and $B$ is the point $(7, 4)$ . There are two points $P$ on the $x$ -axis for which angle $A P B = 9 0^{\circ}$ . What is the distance between these two points?

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Free questions with an explanation for every one, and full timed Cambridge A-Level mock tests.

What is the distance of the point $(5, - 1)$ from the line $3 x + 4 y + 8 = 0$ ?
What is the distance of the point $(- 1, 4)$ from the line $6 x + 8 y + 19 = 0$ ?
What is the distance of the point $(2, 4)$ from the line $5 x + 12 y + 2 = 0$ ?
What is the distance of the point $(5, - 3)$ from the line $3 x + 4 y + 11 = 0$ ?
What is the distance of the point $(6, 3)$ from the line $6 x + 8 y + 7 = 0$ ?
What is the distance of the point $(0, 5)$ from the line $5 x + 12 y - 12 = 0$ ?