Answer: [tex]x=5[/tex]
Step-by-step explanation:
The area of a rectangle can be found with the following formula:
[tex]A=lw[/tex]
Where "l" is the length and "w" is the width.
In this case you can identify in the figure given in the exercise that:
[tex]l=4x-2\\\\w=3[/tex]
You know that the area of that rectangle is the following:
[tex]A=54[/tex]
Therefore, knowing those values, you can substitute them into the formula and then you must solve for "x" in order to find its value. You get that this is:
[tex]54=(4x-2)(3)\\\\54=12x-6\\\\54+6=12x\\\\\frac{60}{12}=x\\\\x=5[/tex]
