What do you mean about that
R(t) = 4t
A(r) = π(r^2)
a) A(t) = A[r(t)] = π[r(t)]^2 = π[4t]^2 = 16π(t^2)
b) t = 4,
A(4) = 16*3.14*(16)^2 = 12,861.44
D.
None of the above. Because your expression would be, 2 + 0.75 x 6.
Hope it helps. ;)
X=$20/$4
x=5 gallons
x is the amount of gallons.
1 gallon=32 miles
5 gallons=160 miles
Margie can drive 160 miles on $20 of gas