From the given polynomials, identify the polynomials of degree one.

a.11y^2 - 5 - 4y
b.(3x^2)^1/2 + 12
c.7 - (12)^1/2x
d.2x + 13x^2
e.5x + 7y + 8
f.(12)^1x^1
g.x^3 + 2x - 10
h.3x + 4x - 4

Solve the following:
i. 2x = -3x + 9
ii. 3x/5 = -6
iii. y/4 + 2 = 7
iv. 16 = -2x/3
v. Find f(1) for f(x) = 2x^3 - 3x^2 + x - 21
vi. A function gives the value of C as 2 × (22/7) × r. Find C when r = 7 cm and r = 91 cm.

I know that I have to use the substitution methode and the elimination. I am not sure if I applied the correct system.