Help please and simplify answer in radical form if needed

Find the solution of system of equation y= x-4 y=4x+2

Afactory buys 10% of its components from suppliers b and the rest from supplier c. it is known that 6% of the components it buys are faulty. of the components brought from suppliers a,9% are faulty and of the components bought from suppliers b, 3% are faulty. find the percentage of components bought from supplier c that are faulty.

Y+ 2/y is it a polynomial in one variable or not? and if so, why?