Example 1: Solve this system of equations.     6x + 7y = 51     8x - y = 37 Example 2: You are deciding between two cellphone plans. The plan from Alpha Mobile costs $20 per month for unlimited talk and text plus $10 for each gigabyte of data used. The plan from Beta Cellular costs $50 per month for unlimited talk and text plus $5 per month for each gigabyte of data used. How much data do you need to use each month to make Beta Cellular the better option? Work in small groups to find a solution and write up an explanation of your answer.