Help me solve for x again

Can someone check if i did this right since i really want to make sure it’s correct. if you do you so much

Suppose that the price p, in dollars, and the number of sales, x, of a certain item follow the equation 4 p plus 4 x plus 2 pxequals56. suppose also that p and x are both functions of time, measured in days. find the rate at which x is changing when xequals2, pequals6, and startfraction dp over dt endfraction equals1.5.

Percent increase and decrease. original number: 45 new number: 18