Question

Encontre as raízes de cada uma das equações incompletas abaixo:

Answer 1

Resposta:

a) $-x^2=-81\\x^2=81\\x=\pm \sqrt{81}\\x=\pm9$          b) $5x^2=125\\x^2=\frac{125}{5}\\x^2=25\\x= \pm \sqrt{25}\\x=\pm 5$        c) $3x^2=48\\x^2=\frac{48}{3}\\x^2=16\\x=\pm \sqrt{16}\\x=\pm 4$        d) $2x^2=128\\x^2=\frac{128}{2}\\x^2=64\\x=\pm \sqrt{64}\\x= \pm 8$

e) $-2x^2=-4\\x^2=\frac{-4}{-2}\\x^2=2\\x=\pm \sqrt2$          f) $-x^2=-49\\x^2=49\\x=\pm \sqrt{49}\\x=\pm7$        g) $x^2=64\\x=\pm \sqrt{64}\\x=\pm 8$        h) $11x^2=44\\x^2=\frac{44}{11}\\x^2=4\\x=\pm \sqrt4\\x=\pm 2$

i) $x^2=121\\x=\pm \sqrt{121}\\x=\pm 11$           j) $x^2=1\\x=\pm \sqrt1\\x=\pm 1$            k) $4x^2=100\\x^2=\frac{100}{4}\\x^2=25\\x= \pm \sqrt{25}\\x=\pm5$