In a triangle ABC, ĐA = 600, a = 4 and b = 3, then c is a ro... | MATH - RELATION BETWEEN SIDES & ANGLES, SOLUTION OF TRIANGLES | SolveeIt | Solveeit

Today, August 19

Question

In a triangle ABC, ĐA = 60⁰, a = 4 and b = 3, then c is a root of the equation

A

c² + 3c + 7 = 0

B

c² –3c + 7 = 0

C

c² + 3c –7 = 0

D

c² –3c –7 = 0

Answer

c² –3c –7 = 0

Explanation

Solution

cos 60⁰ = ̃ c² –3c – 7 = 0

̃ choice (4) is correct.