The value of x is 17.6. She should have added 5.4 on both sides to get the correct value of x. Then the correct option is A.
What is the linear system?
A Linear system is a system in which the degree of the variable in the equation is one. It may contain one, two, or more than two variables.
Kaitlyn solved the equation for x using the following calculations.
[tex]\rm -5.4 + x =12.2[/tex]
and she did the calculation will be
[tex]\rm -5.4x = 6.8[/tex]
The mistake she did in this equation is the plus sign is removed between the -5.4 and x. And she subtracted 5.4 from 12.2.
The correct solution of the equation is to add both sides 5.4. Then we have
[tex]\begin{aligned} \rm -5.4 + x+5.4 &=12.2+5.4\\\\\rm x &= 17.6\end{aligned}[/tex]
More about the linear system link is given below.
https://brainly.com/question/20379472