Question

Which point in the diagram at the right had a distance of sq of 130

Answer 1

S

Explanation:

the distance formula (Pythagoras on the right-angled triangle of the coordinate differences) says that

sqrt²(130) = 130 = (-5 - x)² + (5 - y)²

let's try Q

130 = (-5 - 5)² + (5 - 2)² = (-10)² + 3² = 100 + 9 = 109

no, wrong.

let's try S

130 = (-5 - 4)² + (5 - -2)² = (-9)² + 7² = 81 + 49 = 130

correct !