Question

determine o valor de x nos casos​

Answer 1

Letra a)

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

Letra b)

${a}^{2} = {b}^{2} + {c}^{2} \\ {13}^{2} = {5}^{2} + {x}^{2} \\ 169 = 25 + {x}^{2} \\ - {x}^{2} = 25 - 169 \\ - {x}^{2} = - 144 \: \: \: .( - 1) \\ {x}^{2} = 144 \\ x = \sqrt{144} \\ x = 12$

Letra c)

${a}^{2} = {b}^{2} + {c}^{2} \\ {4}^{2} = {3 }^{2} + {x}^{2} \\ 16 = 9 + {x}^{2} \\ - {x}^{2} = 9 - 16 \\ - {x}^{2} = - 7 \: \: \: .( - 1) \\ {x}^{2} = 7 \\ x = \sqrt{7} \: \: \: \: ou \: \: \: x = 2.64$

Letra d)

${a}^{2} = {b}^{2} + {c}^{2} \\ {6}^{2} = {3}^{2} + {x}^{2} \\ 36 = 9 + {x}^{2} \\ - {x}^{2} = 9 - 36 \\ - {x}^{2} = - 27 \: \: \: .( - 1) \\ {x}^{2} = 27 \\ x = \sqrt{27} \: \: \: ou \: \: \: x = 5.19$