Pls help me kind sir or madam

Answer:
[tex] 7 {t}^{2} + 21t[/tex]
Step-by-step explanation:
There are total 7 rectangles of same dimensions.
[tex] \therefore \: Area \: of \: pattern \\ = 7 \times Area \: of \: one \: rectangle \\ = 7t(t + 3) \\ = 7 ({t}^{2} + 3t) \\ = 7 {t}^{2} + 21t \\ \\ \red{ \bold{Area \: of \: pattern = 7 {t}^{2} + 21t }}\\ [/tex]