Answer:
 6 t + 4  p   ≤  150   is the required inequality.
Step-by-step explanation:
Here, the area required for 1 tomato plant = 6 sq ft
So, the area required to plant t tomato plants  
= t x ( Area required by 1  tomato plant)   = t x ( 6 sq ft)  = 6 t
the area required for 1 pepper plant = 4 sq ft
So, the area required to plant p  pepper plants  
= p x ( Area required by 1  pepper plant)   = p x ( 4 sq ft)  = 4 p
Now, total area of the garden = 150 Sq ft.
Also, area of p pepper pants + t tomato plants =   (6 t +  4 p) sq ft
So, now according to the question:
Total area of both plants ≤ Total area of the garden
⇒ (6 t +  4 p) sq ft   ≤  150 sq ft
or, 6 t + 4  p   ≤  150   is the required inequality.