Question

1 ) Calcule o valor de x, nas figuras abaixo: ​

Answer 1

Resposta:

a) x=15

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

b)x=6

$10^{2} =8^{2}+x^{2} \\100=64+x^{2} \\100-64=x^{2} \\36=x^{2} \\\sqrt{36} =6$

c)x=3

$5^{2} =4^{2} +x^{2} \\25=16+x^{2} \\25-16=x^{2} \\9=x^{2} \\\sqrt{9}=3$

d)x=$\frac{400}{7}$

$20^{2} = 3x+4x\\400=7x\\\frac{400}{7} =x$

Answer 2

Explicação passo-a-passo:

a)

$x^{2}=9^{2}+12^{2}$ =>

$x^{2}=81+144$ =>

$x^{2}=225$ =>

$x=\sqrt{225}$ =>

x = 15

b)

$10^{2}=x^{2}+8^{2}$ =>

$100=x^{2}+64$ =>

$x^{2}=100-64$ =>

$x^{2}=36$ =>

$x=\sqrt{36}$ =>

x = 6

c)

$5^{2}=x^{2}+4^{2}$ =>

$25=x^{2}+16$ =>

$x^{2}=25-16$ =>

$x=\sqrt{9}$ =>

x = 3

d)

$20^{2}=(3x)^{2}+(4x)^{2}$ =>

$400=9x^{2}+16x^{2}$ =>

$25x^{2}=400$ =>

$x^{2}=\frac{400}{25}$ =>

$x=\sqrt{16}$ =>

x = 4