Question

if the sum of two integers is -40 if the first integers is 35 find the other integer

Answer 1

$a + b = - 40 \\ 35 + b = - 40 \\ b = - 75$
other integer is -75

Answer 2

Let the integers be x and y
X+Y=-40
If one is 35 then the other =
X+Y=-40
35+Y=-40
Y=-40-35
Y=-75
So the other number is -75