Ihave to solve the problem y= x -7 and 2x+y=8 using substitution. i'm not sure how

Language arts : : which answer choice is correctly punctuated? question 2 options: a. for the apartment we need lamps rugs pictures, and pillows. b.mom is giving us some dishes, utensils and pots. c.did you remember to shop for soap, tissues and, paper towels? d.yes, i bought cleaning supplies, first aid items, and light bulbs.