1) When will the dependent variable in the equation y=√x+4-3 equal or exceed to 4?

Question

A) x > or equal to -0.17
B) x > or equal to 45
C) x > or equal to 48
D) x > or equal to 53

2) The function t=√d/16 models the time (t) in seconds that an object has been falling after the object has fallen d feet. When will the time be more than 1 minute?
A) d > or equal to 16 ft
B) d > or equal to 225 ft
C) d > or equal to 3,600 ft
D) d > or equal to 57,600 ft

I do not know how to solve these questions. I am quite confused and help would mean a lot to me. Thank you! If you can only solve one question that is extremely fine. :) I just need help.

Answer 1

#1
√(x+4)-3 >= 4
√(x+4) >= 7
x+4 >= 49
x >= 53

#2
t = √(d/16), so we want (using t in seconds)

√(d/16) > 60
d/16 > 3600
d > 57600

Answer 2

Thank you so much! I really appreciate all your help.

Answer 3

For number one I think the answer should be 45 because Steve added 4 instead of subtracting 4!!!!