Question

What two numbers add to -1 but subtract to 9

Answer 1

4 and -5.

Explanation:

4 + -5 = 4-5

4-5= -1

4 - -5= 4+5

4+5 = 9

Answer 2

Answer: 4 and -5

Explanation:

setup the simultaneous equations and solve them
a + b = -1
a - b = 9

adding the two equations 2a = 8 so a = 4 which means that b = -5