Question

please ans it plssss... I will mark the right answer as brainliest plzzzzzz ​

Answer 1

Answer 1:

semi perameter = sum of all side / 2

                          = $\frac{3+4+5}{2}$

                          = $\frac{12}{2}$

                          = 6cm

Answer 2:

Refer the image.

Answer 3:

here,

a = 12 cm

b = 12 cm

perimeter = a + b + c

so, 12 + 12 + c = 30

or c = 30 - 24 = 6 cm

semi-perimeter (s) = 30 /2 = 15 cm

area = root [s(s-a)(s-b)(s-c)]

= root [15(15 - 12)(15 - 12)(15 - 6)]

= root [15 *3*3*9]

= root [15 * 9*9]

= 9 root 15 cm2