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MathsMediumMCQ2018 · 16 Apr Online

Q69.If a circle C , whose radius is 3, touches externally the circle x2 + y2 + 2x −4y −4 = 0 at the point (2, 2), then the length of the intercept cut by this circle C on the x-axis is equal to (1) 2√3 (2) √5 (3) 3√2 (4) 2√5

What This Question Tests

This question requires finding the equation of a circle given its radius and a point of external tangency with another circle, and then calculating the length of the intercept made by this circle on the x-axis.

Concepts Tested

Equation of a circleExternal touch conditionIntercept on x-axis

Formulas Used

(x-h)^2 + (y-k)^2 = r^2

Distance between centers = r1 + r2

Length of x-intercept = 2 * sqrt(g^2 - c)

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