What is the simplified form of the following expression?
i need this asap

What is the solution to the system of the equations? x = y - 3 x + 3y = 13

Tomas is making trail mix using granola and walnuts. he can spend a total of $12 on the ingredients. he buys 3 pounds of granola that costs $2.00 per pound. the walnuts cost $6 per pound. he uses the equation to represent the total cost, where x represents the number of pounds of granola and y represents the number of pounds of walnuts. he solves the equation for y, the number of pounds of walnuts he can buy. answer- b tomas added 6 to both sides of the equation instead of subtracting 6. just took the test

On average, how many more hits will he get when he bats 100 times at home during the day as opposed to 100 times away at night?