Question

In triangle abc if r1=3 r2=10 r3=15 then c

Answer 1

Given: r1 = 3, r2 = 10, r3 = 15

To find: Value of c?

Solution:

• Now we have given the values of r1, r2 and r3, so in solution of triangles, we know that:
• 1 / r = 1 / r1 + 1 / r2 + 1 / r3

          1 / r = 1 / 3 + 1 / 10 + 1 / 15

          1 / r = 10 + 3 + 2 / 30

          1 / r = 15 / 30

          r = 2

• Also, we know that:

• Δ² = r x r1 x r2 x r3

         Δ² = 2 x 3 x 10 x 15

         Δ² = 900

         Δ = √900

         Δ = 30

• Now, r = Δ/s

         s = Δ/r

         s = Δ / r = 30 / 2 = 15

         r3 = Δ / (15 - c)

         15 = 30 / (15-c)

         15 - c = 2

         c = 15 - 2

         c = 13

Answer:

            So the value of c is 13.