Question

Calcule a área de cada triângulo
B)12 dm;16 dm
C)20 dm;15 dm;12 dm

Answer 1

Resposta:

b) 96dm²

c) 150dm²

Explicação passo-a-passo:

b)

$A = \frac{b \times h}{2} \\\\ A = \frac{12 \times 16}{2} \\\\\ A = \frac{192}{2} \\\\ A =96$

c)

${15}^{2} = {12}^{2} + {x}^{2} \\ 225 = 144 + {x}^{2} \\ {x}^{2} = 225 - 144 \\ {x}^{2} = 81 \\ x = \sqrt{81} \\ x = 9$

${20}^{2} = {12}^{2} + {x}^{2} \\ 400= 144 + {x}^{2} \\ {x}^{2} = 400 - 144 \\ {x}^{2} = 256 \\ x = \sqrt{256} \\ x = 16$

$A = \frac{b \times h}{2} \\\\ A = \frac{(9 + 16) \times 12}{2} \\\\\ \ A = \frac{25\times 12}{2} \\\\\ A = \frac{300}{2} \\\\ A =150$