Do you have a calculator? you can solve it by substituting x.
y=16x^2
0: y = 16(0)^2 = 16(0) = 0
(x = 0 , y = 0)
0.5: y = 16(0.5)^2 = 16(0.25) = 4
(x = 0.5 , y = 4)
1: y = 16(1)^2 = 16(1) = 16
(x = 1 , y = 16)
1.5: y = 16(1.5)^2 = 16(2.25) = 36
(x = 1.5 , y = 36)
2: y = 16(2)^2 = 16(4) = 64
(x = 2 , y = 64)
2.5: y = 16(2.5)^2 = 16(6.25) = 100
(x = 2.5 , y = 100)
3 : y = 16(3)^2 = 16(9) = 144
(x = 3 , y = 144)
4: y = 16(4)^2 = 16(16) = 256
(x = 4 , y = 256)
if you multiply a negative number by itself, it will become positive. So, -4, -3, -2.5, -2, -1.5, -1, -0.5 will be the same as the positive 4, 3, 2.5, 2, 1.5, 1, 0.5.
I'm not sure about the pattern, but if you graph it, it'll be symmetrical across the y-axis.