The original area of a face would be a^2. Now that you added b to the edge, the new area of each face would be (a+b)^2. To find how much the are increased, subtract a^2 from (a+b)^2. 
So the answer is b(2a+b)
Answer:
Option D
Step-by-step explanation:
I dont really know but i think its D
Answer:
Three circular arcs of radius $5$ units bound the region shown. Arcs $AB$ and $AD$ are quarter-circles, and arc $BCD$ is a semicircle.
Step-by-step explanation:
Step-by-step explanation:
Square both sides of the equation.
Let n represent the amount Colin earned on Sunday.
On Sat. he earned n/2; on Sun. he earned n; and on Friday he earned (1/2)(n/2).
Then n/2 + n + n/4 = $70
Mult. all terms by 4 to eliminate fractions:
2n + 4n + n = $280
7n = $280 => n = $40
Colin earned n/2, or $20, on Saturday; n, or $40, on Sunday; and n/4, or $10, on Friday.
Note that $20 and $40 and $10 add up to $70, as they must.
