Explanation:
1) : x = +-3
2): x=4.83 and x = -0.83
3): x= +-3.83
4): x=-8 and x =0
1st one is correct.
for second one
2(x-2)²=16
or, (x-2)² = 8
so, x = 4.83
again,
now
3x²+4=48
or, 3x² = 44
or, x² = 44/3
so, x = 3.83
again
3(x+4)²=48
or, (x+4)² = 16
or, x+4 = 4
so, x = 0
or
x+4 = -4 (since root under 16 is also -4)
x = -8