KnowledgeBoat Logo

Mathematics

In the figure (i) given below, two circles with centers C, D intersect in points P, Q. If length of common chord is 6 cm and CP = 5 cm, DP = 4 cm, calculate the distance CD correct to two decimal places.

In figure, two circles with centers C, D intersect in points P, Q. If length of common chord is 6 cm and CP = 5 cm, DP = 4 cm, calculate the distance CD correct to two decimal places. Circle, ML Aggarwal Understanding Mathematics Solutions ICSE Class 9.

Circles

5 Likes

Answer

From figure,

In figure, two circles with centers C, D intersect in points P, Q. If length of common chord is 6 cm and CP = 5 cm, DP = 4 cm, calculate the distance CD correct to two decimal places. Circle, ML Aggarwal Understanding Mathematics Solutions ICSE Class 9.

PM = MQ = 62\dfrac{6}{2} = 3 cm.

In right △CMP,

⇒ CP2 = CM2 + PM2 (By pythagoras theorem)

⇒ 52 = CM2 + 32

⇒ CM2 = 25 - 9

⇒ CM2 = 16

⇒ CM = 16\sqrt{16} = 4 cm.

In right △DMP,

⇒ DP2 = DM2 + PM2 (By pythagoras theorem)

⇒ 42 = DM2 + 32

⇒ DM2 = 16 - 9

⇒ DM2 = 7

⇒ DM = 7\sqrt{7} = 2.65 cm.

CD = CM + MD = 4 + 2.65 = 6.65 cm.

Hence, CD = 6.65 cm.

Answered By

2 Likes


Related Questions