Question

find the area of s triangle two sides of which are 18cm 10cm and the perimeter is 42cm​

Answer 1

Step-by-step explanation:

18 +10+x=43

x=43 -28

15 cm

So Area =1/2×b×h

1/2×15×18×10

=1350

Answer 2

Answer:

21\sqrt{11}\\

Step-by-step explanation:

a = 18

b = 10

p = 42

  = a + b + c

a + b + c = 42

c + 28 = 42

c = 14

s = p/2 = 21

Using Heron's formula,

Area =

$\sqrt{s(s-a)(s-b)(s-c)}\\= \sqrt{21(21-18)(21-10)(21-14)}\\= \sqrt{21(3)(11)(7)}\\\\= 21\sqrt{11}$