Question

Two different plants grow each year at different rates, which are represented by the functions f(x) = 4x and g(x) = 5x + 2. What is the first year the f(x) height is greater than the g(x) height?

A. Year 0
B.Year 1
C.Year 2
D.Year 3

Can i get some help plz

Answer 1

@ali2x2

Answer 2

@Michele_Laino can u help me plz

Answer 3

you have to substitute x=0, 1,2,3 then you have to compare the values f(x) and g(x) for each year.
For example, if x=0, then we have:
f(0) = 4*0 =0, and g(0)= 5*0+2=2, so f(0) < g(0)
now, please do the same for other values of x

Answer 4

so pu 4 in for f in the problem and 5 in for g

Answer 5

u there

Answer 6

yes!

Answer 7

question:
are f(x) and g(x) heights or rates?

Answer 8

rates

Answer 9

so, are you familiar with differential calculus?

Answer 10

no i am not ?

Answer 11

if f(x) is a rate, then the corresponding height h, is given solving this differential equation:
\[\Large \frac{{dh}}{{dx}} = 4x\]

Answer 12

ok i am trying to understand what is going on but for my first answer i put B. am i right

Answer 13

I'm pondering...

Answer 14

okay

Answer 15

my reasoning is:
height h1 for f(x) is:
\[\Large {h_1}\left( x \right) = 2{x^2}\]
whereas height h2 for g(x) is:
\[\Large {h_2}\left( x \right) = \frac{{5{x^2}}}{2} + 2x\]
and we have h2>h1, if x>0, whereas h2=h1 if x=0

Answer 16

please wait I ask to another helper

Answer 17

so A

Answer 18

@Astrophysics please help

Answer 19

@vera_ewing @nincompoop please help

Answer 20

so what i need to do

Answer 21

This doesn't really make sense, are the functions
\[f(x)=4x~~and~~g(x) = 5x+2~~~~or~~~~f(x)=4^x~~~~and~~~g(x) = 5x+2\]

Answer 22

Two different plants grow each year at different rates, which are represented by the functions f(x) = 4x and g(x) = 5x + 2. What is the first year the f(x) height is greater than the g(x) height?


this is the problem

Answer 23

What are the functions...from what i showed you

Answer 24

is it to the power of x or just times x...

Answer 25

just times

Answer 26

So it's \[f(x) = 4x\] and \[g(x) = 5x+2\]

Answer 27

i am so confused tho

Answer 28

Can you please take an image of your question and post it

Answer 29

i dont know how to do thatfrom computer

Answer 30

Two different plants grow each year at different rates, which are represented by the functions f(x) = 4x and g(x) = 5x + 2. What is the first year the f(x) height is greater than the g(x) height?

Year 0
Year 1
Year 2
Year 3

Answer 31

Ok all I am asking you is, what are the functions they gave you in the problem f(x), if it's to the power of x or is just 4x...

Answer 32

and same for g(x)