Help me with this please!

Achemist has 200 ml of a 10% sucrose solution. she adds x ml of a 40% sucrose solution. the percent concentration, y, of the final mixture is given by the rational function: the chemist needs the concentration of the final mixture to be 30%. how many milliliters of the 40% solution should she add to the 10% solution to get this concentration?

Explain how you do each step what term makes it inconsistent y=2x - 4 ?

Can someone me with the property questions for 12 13 and 14 plz