1) y-4 = -8(x-1)
y-4 = -8x+8
y = 12-8x
It's Linear
2) y= x⁴
It's non-linear
3)y-x² = 4.5
y = 4.5+x²
It's non-linear
4)3x+5y=15
3x=15-5y
It's Linear.
So, Among your all parts of the question,
Linear equations are: 1st & 4th
Non-Linear equations are: 2nd & 3rd
Hope this helps!