Question

Find the area of the triangular notice board, whose sides are 9cm,12 cm and 15 cm.​

Answer 1

Answer:

$A = \sqrt{s(s - a)(s - b)(s - c)} </p><p></p><p>$

$s = \frac{a + b + c}{2}$

$A = \frac{1}{4} \sqrt{ - a^4 + 2(ab)^2+ 2(ac)^2 - b^4 + 2(bc)^2 - c^4}$

$= \frac{1}{4} \sqrt{ - 9^4 + 2.(9.12)^2 + 2.(9.15)^2 - 12^4 + 2.(12.15) - 15^4}$

=54cm²