Create an equivalent system of equations using the sum of the system and the first equation.
x + 4y = 8
4x + y = 2
ox + 4y = 8
5x + y = 2
ox + 4y = 8
5x + 5y = 2
ox + 4y = 8
4x + 5y = 10
ox + 4y = 8
5x + 5y = 10

2^y = ln 5, or   y(ln 2) = ln 5.   solving for y,   y = (ln 5) / (ln 2).   y=5

step-by-step explanation:

the circle graph is not a function.

step-by-step explanation:

the graph of the circle is not a function.

because for a graph to be a function, each value of x must give one value of y

in the circle, the values of x for -2< x< 2 each give 2 values of y.

hence this is not a function.