I don't know what equation use nor how to find the answer. we are learning about margin of error in stats :)

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

What are the solutions of the system? solve by graphing. y = -x^2 -6x - 7 y = 2

Aline passes through 3,7 and 6,9 what equation represents the line