Question

X + a = b what happens to x if a increases and b remains the same

Answer 1

$x+a=b\\ x=b-a$
So if a increases, the x decreases.

Answer 2

Lets find out....lets say a = 4 and b = 2

x + a = b
x + 4 = 2
x = 2 - 4
x = -2

now.....what happens to x if a increases and b stays the same...
lets let a = 5 and b will still be 2...
x + a = b
x + 5 = 2
x = 2 - 5
x = -3

according to this, x will be smaller

lets check again...with negatives
x + a = b...x = -3 and b = 2
x - 3 = 2
x = 5

now x = -2 and b = 2
x + a = b
x - 2 = 2
x = 4

yep.....x gets smaller