857 runners entered a race. 354 more entered before the race started. How many runners are in the race?

Can someone me and do the problem plz so i can understand it more better

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10

Select the correct answer from each drop-down menu. the length of a rectangle is 5 inches more than its width. the area of the rectangle is 50 square inches. the quadratic equation that represents this situation is the length of the rectangle is inches.