[tex]\large\text{$A ~\acute{a}rea ~do ~tri\hat{a}ngulo ~ \Rightarrow ~A = 30 ~cm^2 $}[/tex]
[tex]\large\text{$Letra ~a) ~A = 30 ~cm^2 $}[/tex]
Encontrar a altura do triângulo ( outro cateto ).
[tex]b^2 = h^2 - c^2\\\\b^2 = 13^2 - 5^2\\\\b^2 = 169 - 25\\\\b^2 = 144\\\\b = \sqrt{144} \\\\b = 12 ~cm[/tex]
A área do triângulo:
[tex]A = \dfrac{base ~. ~altura}{2} \\\\\\A = \dfrac{b ~. ~h}{2} \\\\\\A = \dfrac{5 ~. ~12}{2} \\\\\\A = \dfrac{60}{2} \\\\\\A = 30 ~cm^2[/tex]
===
Para saber mais:
https://brainly.com.br/tarefa/49634383
https://brainly.com.br/tarefa/49819065
https://brainly.com.br/tarefa/49814998
