Eight times a number plus five times another number is - 13. the sum of the two numbers is 1. what are the numbers?

7 and - 6 because ... 8x+5y=-13x+y=1-y - yx=1-y and you can substitute this into the first equation8 (1-y) + 5y=-138-8y+5y=-138-3y=-13-8 - 8-3y=-21/-3 / - 3y=7

x+7=1-7 - 7x=-6So the two numbers are 7 and - 6.