a)
\(\sqrt{x}=7\Rightarrow x=49\)
b) \(\sqrt{2}-3x=4\Rightarrow3x=\sqrt{2}-4\)
\(x=\frac{\sqrt{2-4}}{3}\)
c)suy ra \(\frac{x+1}{2}=\frac{3}{2}\)suy ra x+1=3 suy ra x=2
a/ \(\sqrt{x}=5-2=7\)7
mà \(\sqrt{49}=7\)
=> x = 49
b/\(\sqrt{2}\)gần bằng 1,41
\(\sqrt{2}-4=3x\)
\(1,41-4=3x\)
\(-2,86=3x\)
\(x=-2,86:3=-0.9\left(3\right)\)