Question

I didn't understand why we have to divide both the equations???
pls pls pls pls tell me for points

1) The compound interest for 2 years and 3 years on certain principal at certain
rate of interest are ? 8820 and 9261 respectively. Find the rate of interest
and the principal.

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Answer 1

Two diameters AB and CD intersect each other at O. AC, CB and BD are joined

∠DBA = 50°

∠DBA and ∠DCA are in the same segment

∴ ∠DBA = ∠DCA = 50°

In ∆OAC, OA = OC (Radii of the circle)

∴ ∠OAC = ∠OCA = ∠DCA = 50°

and ∠OAC + ∠OCA + ∠AOC = 180° (Sum of angles of a triangle)

⇒ 50° + 50° + ∠AOC = 180°

⇒ 100° + ∠AOC = 180°

⇒ ∠AOC = 180° – 100° = 80°

Hence ∠AOC = 80°