If [tex][tex]$h(x) = x^2 - 3$[/tex][/tex] and [tex][tex]$k(x) = 5 + x$[/tex][/tex], what is [tex][tex]$k(h(7))$[/tex][/tex]?

A. 49
B. 51
C. -23
D. -35



Answer :

To solve the problem, let's break it down step-by-step.

1. Define the functions [tex]\( h(x) \)[/tex] and [tex]\( k(x) \)[/tex]:
[tex]\[ h(x) = x^2 - 3 \][/tex]
[tex]\[ k(x) = 5 + x \][/tex]

2. Calculate [tex]\( h(7) \)[/tex]:
We substitute [tex]\( x = 7 \)[/tex] into the function [tex]\( h(x) \)[/tex]:
[tex]\[ h(7) = 7^2 - 3 \][/tex]
Calculate [tex]\( 7^2 \)[/tex]:
[tex]\[ 7^2 = 49 \][/tex]
Then subtract 3:
[tex]\[ 49 - 3 = 46 \][/tex]
So, [tex]\( h(7) = 46 \)[/tex].

3. Calculate [tex]\( k(h(7)) \)[/tex], which is [tex]\( k(46) \)[/tex]:
We substitute [tex]\( x = 46 \)[/tex] into the function [tex]\( k(x) \)[/tex]:
[tex]\[ k(46) = 5 + 46 \][/tex]
Adding the numbers together:
[tex]\[ 5 + 46 = 51 \][/tex]
So, [tex]\( k(46) = 51 \)[/tex].

Therefore, the value of [tex]\( k(h(7)) \)[/tex] is [tex]\( 51 \)[/tex].

The correct answer is:

[tex]\[ \boxed{51} \][/tex]