Answer:
(a) 
(b) 
Step-by-step explanation:
(a) Write and simplify an expression for the exact area of the sidewalk.
(b) Find the approximate area of the sidewalk. Use 3.14 to approximate .
(a) The sidewalk area is the difference in the area of outer circle and inner circle.
Use formula
for the area of the circle:

The difference is

(b) Use approximation
then

Answer:
2t-7
Step-by-step explanation:
distribute the 2, to the t and the -4
you should have 2t-8+1
then you add the 1 to the -8 and you get -7
resulting in 2t-7 being the answer
15 squares are needed to make the eighth figure in the pattern
Answer:
?
Step-by-step explanation:
Where's the circle?