Please someone help me

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?

Kendra had twice as much money as kareem. kendra later spent $8 and kareem earned $6. by then,the two had the same amount of money. how much money did each have originally?

How does the graph of g(x)=⌊x⌋−3 differ from the graph of f(x)=⌊x⌋? the graph of g(x)=⌊x⌋−3 is the graph of f(x)=⌊x⌋ shifted right 3 units. the graph of g(x)=⌊x⌋−3 is the graph of f(x)=⌊x⌋ shifted up 3 units. the graph of g(x)=⌊x⌋−3 is the graph of f(x)=⌊x⌋ shifted down 3 units. the graph of g(x)=⌊x⌋−3 is the graph of f(x)=⌊x⌋ shifted left 3 units.