Given the above, evaluate g(-r) if r = -7.

Question

g(r)=   
 4|r|  if  r \geq 2 
 |r|  if  r <  2

(A) –28
(B) –14
(C) –7
(D) 7
(E) 28

IanStewart · Answer

If r = -7, then -r = 7, and g(-r) = g(7). By the definition of the function g, since 7 > 2, g(7) = 4 |7| = 28.

alwaysHP · Answer

g(r) = 4|r| if r>= 2
put -r in place of r

g(-r) = 4|-r| - r>= 2 which is r <= 2

This satisfies the condition and it becomes

4*7 = 28

BrushMyQuant · Answer

\begin{g(r)=}
\begin{equation*}
\begin{cases}
4|r| \ if \ r \geq 2 \
|r| \ if \ r < 2 \
\end{cases}
\end{equation*}

And we are asked to find the value of g(-r) when r=-7

Let's put r=-7 first in g(-r) we get
g(-r) = g(-(-7)) = g(7)

Now, to find g(7) we need to check the condition when r >= 2 as (7 >= 2)

=> g(7) = 4|7| = 4*7= 28 ( Watch this video to learn about the basics of Absolute Value )

So, answer will be E
Hope it helps!

Watch the following video to learn the Basics of Functions

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

MathRevolution · Answer

g(-r) at r = -7 is g(-(-7)) = g(7).

As per the given condition it will be 4 * 7 = 28

Answer E

bumpbot · Answer

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Given the above, evaluate g(-r) if r = -7.

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Given the above, evaluate g(-r) if r = -7.

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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