Answer:
y=1/2x=6 - linear, written as y=mx+b.
y=(x-5)^2 - nonlinear, x has an exponent greater than 1
y=2^x+8 - nonlinear, x is an exponent
y=3(x+7) - linear, can be written as y=mx+b (y=3x+21)
y=4x^3-1 - nonlinear, x has an exponent greater than 1
Step-by-step explanation: