Question

Gente me ajudem pfv! (dou pontos)
responda se souber, se não souber não vem falar que não sabe para roubar os pontos, irei denunciar!
resolva as equações do segundo grau incompletas:
a)x²-25=0
b)x²-100=0
c)2x²-900=0
d)3x-75=0
e)x²-625=0
f)x²289=0
g)x²-529=0
h)x²-1225=0
i)x²-2=0
​

Answer 1

$\large\boxed{\begin{array}{l}\sf a)~ x^2-25=0\\\sf x^2=25\\\sf x=\pm\sqrt{25}\\\sf x=\pm5\implies S=\{-5,5\}\\\sf b)~x^2-100=0\\\sf x^2=100\\\sf x=\pm\sqrt{100}\\\sf x=\pm10\implies S=\{-10,10\}\\\sf c)~2x^2-900=0\\\sf 2x^2=900\\\sf x^2=\dfrac{900}{2}\\\sf x^2=450\\\sf x=\pm\sqrt{450}\\\sf x=\pm\sqrt{225\cdot2}\\\sf x=\pm15\sqrt{2}\implies S=\{-15\sqrt{2},15\sqrt{2}\}\end{array}}$

$\large\boxed{\begin{array}{l}\sf d)~3x^2-75=0\\\sf 3x^2=75\\\sf x^2=\dfrac{75}{3}\\\\\sf x^2=25\\\sf x=\pm\sqrt{25}\\\sf x=\pm15\implies S=\{-15,15\}\\\sf e)~ x^2-625=0\\\sf x^2=625\\\sf x=\pm\sqrt{625}\\\sf x=\pm25\implies S=\{-25,25\}\\\sf f)~ x^2-289=0\\\sf x^2=289\\\sf x=\pm\sqrt{289}\\\sf x=\pm17\implies S=\{-17,17\}\end{array}}$

$\large\boxed{\begin{array}{l}\sf g)~x^2-529=0\\\sf x^2=529\\\sf x=\pm\sqrt{529}\\\sf x=\pm23\implies S=\{-23,23\}\\\sf h)~ x^2-1225=0\\\sf x^2=1225\\\sf x=\pm\sqrt{1225}\\\sf x=\pm35\implies S=\{-35,35\}\\\sf i)~ x^2-2=0\\\sf x^2=2\\\sf x=\pm\sqrt{2}\implies S=\{-\sqrt{2},\sqrt{2}\}\end{array}}$