I’m so bad at math Can someone help

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

Can some one explain this i got sent this. is this a threat i’m scared

The table below shows the approximate height of an object x seconds after the object was dropped. the function h(x)= -16x^2 +100 models the data in the table. for which value of x would this model make it the least sense to use? a. -2.75 b. 0.25 c. 1.75 d. 2.25