Answer:
The answer is 6x² - 21x.
Step-by-step explanation:
You have to substitute the expressions inro the formula :
[tex]A = length \times width[/tex]
[tex]let \: l = 2x - 7,w = 3x[/tex]
[tex]A = (2x - 7) \times 3x[/tex]
[tex]A = 3x(2x - 7)[/tex]
[tex]A = 6 {x}^{2} - 21x[/tex]