Answer:
6
Step-by-step explanation:
Here it's given that ,
[tex]\sf\red{\longrightarrow} A=\sqrt{s(s-a)(s-b)(s-c)}[/tex]
Also ,
[tex]\sf\red{\longrightarrow} s =\dfrac{a+b+c}{2}[/tex]
And we need to find out the value of A , when
So , on substituting the respective values to find s we have ,
[tex]\sf\red{\longrightarrow} s =\dfrac{3+4+5}{2}=\dfrac{12}{2}=\bf{6}[/tex]
Now let's find out A as ,
[tex]\sf\red{\longrightarrow} A = \sqrt{6(6-3)(6-4)(6-5)} \\[/tex]
[tex]\sf\red{\longrightarrow}A =\sqrt{6 * 3 * 2 * 1}\\[/tex]
[tex]\sf\red{\longrightarrow} A = \sqrt{3^2 * 2^2 *1^2}\\[/tex]
[tex]\sf\red{\longrightarrow}A = 3*2\\[/tex]
[tex]\sf\red{\longrightarrow}\boxed{\qquad \blue{\bf A = 6 \qquad}}[/tex]