Question

Is it possible for two numbers to have a difference of 8, and a sum of 1?

Answer 1

Let x be the first number and y be the second number. If a difference of these numbers is 8, then x-y=8. If a sum of these two numbers is 1, then x+y=1.

Solve the system of equations $\left \{ {{x-y=8} \atop {x+y=1}} \right.$ by adding two equations:

$x-y+x+y=8+1,\\ 2x=9,\\ x=4.5$.

Hence y=1-x=1-4.5=-3.5.

Answer: the difference of 4.5 and -3.5 is 8 and the sum is 1.