Answer:
13√731 cm²
Step-by-step explanation:
Heron
A = √p(p-a)(p-b)(p-c)
p = (a+b+c)/2 = (30+30+26)/2 = 86/2 = 43
A = √43*(43-30)(43-30)(43-26)
= √43*13*13*17
= 13√43*17
= 13√731 cm²
Phytaghora
h = √30² - 13²
= √900 - 169
= √731
A = h × b/2
= √731 × 26/2
= 13√731 cm²
