Answer:the number is 25
Step-by-step explanation:
2a-7=43
Collect like terms
2a=43+7
2a=50
Divide both sides by 2
2a/2=50/2
a=25
Answer:
78.5 ft²
Step-by-step explanation:
In this situation, the dog's 5 ft leash is the radius of the circle that he forms.
So, the radius is 5.
Use the area formula, A =
r². Plug in 5 as r, and 3.14 as 
A =
r²
A = (3.14)(5²)
A = (3.14)(25)
A = 78.5
So, the area of the grass he can cover is 78.5 ft²
The volume is 4.19ft³ Hope it helps <3