Identify all of the linear functions

A linear function has highest power (exponent) of a variable as 1.

Option 1) 2x+5y=13   : Power of x and y are 1 there, so it's a linear function.

Option 2) -x^3 =3y+10    : Power of y is 1 but power of x is 3, so it's not a linear function.

Option 3) 3(2x^4+y)=14     :Power of y is 1 but power of x is 4, so it's not a linear function.

Option 4) y=13-2x^2         : Power of y is 1 but power of x is 2, so it's not a linear function.

Option 5) 2=y+x^5             : Power of y is 1 but power of x is 5, so it's not a linear function.

Option 6) y=x+7                 :Power of x and y are 1 there, so it's a linear function.

Therefore, only functions 2x+5y=13 and y=x+7 are linear functions.

the expected value of the random variable : 0, 1 and 2

step-by-step explanation: