To compute the derivatives, treat y {\displaystyle y} as a function of x {\displaystyle x} and use the chain rule every time you need to take its derivative. For example, ( ( y − 5 ) 4 ) ′ = 4 ( y − 5 ) 3 y ′ {\displaystyle ((y-5)^{4})'=4(y-5)^{3}y'} .
