a)
2 [tex]x^{2}[/tex] =98
[tex]x^{2}[/tex]=98 /2
[tex]x^{2}[/tex] =49
[tex]x = \sqrt{49}[/tex]
[tex]x=7[/tex]
b)
[tex]x^{2}[/tex] /4 =36
[tex]x^{2}[/tex]=[tex]36 * 4[/tex]
[tex]x^{2}[/tex]=144
x[tex]=\sqrt{144}[/tex]
[tex]x=12[/tex]
c)
[tex]3x^{2} =9\\x^{2} =9 / 3\\x=\sqrt{3}[/tex]
d)
[tex]4x^{2} =20\\x^{2} =20/4\\x^{2} =5\\x=\sqrt{5}[/tex]