Can someone please check my answer?

Carlos has 4/5 of a tank of fuel in his car. he uses 1/10 of a tank per day. how many days will his fuel last?

What are the solutions of the system? y = x^2 + 2x +3y = 4x - 2a. (-1, -6) and (-3, -14)b. (-1, 10) and (3, -6)c. no solutiond. (-1, -6) and (3, 10)

The perimeter of a rectangle is 42 inches. if the width of the rectangle is 6 inches, what is the length