Please may someone help me with this question thank you

For [tex]f(x) = 4x+1[/tex] and [tex]g(x) = x^{2} -5[/tex] find [tex](f[/tex] ° [tex]g)[/tex][tex](4)[/tex]

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

Jake bakes and sell apple pies. he sells each pie for $5.75 . the materials to make the pies cost $40. the boxes jake puts the pies in cost & 12.50 total. how many pies does jake need to sell to earn a profit of $50