For all numbers x, the function h is defined by h(x) = 2x − 1, and the

Question

For all numbers x, the function h is defined by h(x) = 2x − 1, and the function g is defined by g(x) = (2x − 3)/5. If k is a positive number, what is the value of g(k)?

(1) h(k) = 7

(2) h(1) = k/4

Salsanousi · Answer

Statement 1) tells us the h(k) = 7 from this we can find the value of k and can then substitute it in g(k) to find the value of g(k) so it is sufficient.

For the sake of showing how we get the value h(k) = 7 so this means  2k - 1 = 7  so  2k = 8  and k = 4

substitute k = 4 into g(4) =  \frac{(2*4 - 3)}{5} = \frac{(8-3)}{5} = \frac{5}{5} = 1

Statement 2)

2-1 = \frac{k}{4}  so k = 4 now substitute in g(4) we get the answer.

Answer choice D

nkin · Answer

Question asks us to find g(k) = (2*k-3)/5. Hence, a statement is sufficient if you can find the value of k.

Stmt 1: h(k) = 2*k - 1 = 7 => k can be found, Hence sufficient, Eliminate B, C, E

Stmt 2: h(1) = 2*1 - 1 = k/4 => k can be found, Hence sufficient.

No Need to solve, since it a DS question. Answer is Option D.

BrushMyQuant · Answer

Given that h(x) = 2x − 1 and g(x) = (2x − 3)/5 and we need to find the value of g(k)

Now, to answer this problem we need to find the value of k

STAT 1:  h(k) = 7

=> h(k) = 2k − 1 = 7
=> 2k = 8
=> k =  \frac{8}{2}  = 4
=> g(k) = g(2) = (2*2 - 3)/5 =  \frac{1}{5} 
=>   SUFFICIENT

STAT 2:  h(1) = k/4

h(1) = 2*1 - 1 = 2-1 = 1 = k/4
=> k = 4
=>   SUFFICIENT

So,  Answer will be D 
Hope it helps!

Watch the following video to learn the Basics of Functions and Custom Characters

https://www.youtube.com/watch?v=b7JoMX0gk8M

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