Explanation : Since the circle with centre at the origin, is symmetric about the X-axis, Y-axis, the line X = Y and the line X = - Y, the reflection of (2, 4) about these axes, will also be points on the circle.
Explanation : Translating so that both the scales start at the origin, and scaling so that the divisions in both scales coincide, we get the formula (M-100) x 225/150 = J-75, where M refers to the scale in Mars and J, to the scale in Jupiter.
Putting M = 200,
we get J = 225.