The current area is 15 x 9 = 135 square feet.
He wants to increase both the length and width by X:
Set up an equation:
(15 +x) * (9 +x) = 135 * 2
Simplify :
x^2 + 24x + 135 = 270
Subtract 270 from both sides:
x^2 + 24x - 135 = 0
Use the quadratic formula to solve for x:
-24 +/- √(24^2 - 4(1*-135) / 2*1
x = 4.7 or -28.7
The answer has to be a positive value, so x = 4.7 feet.
Here's the volume formula (and the area formula) typed a little neater than that.
(I'm guessing you forgot to type in your question?)
Answer:
C. 4x+12
Step-by-step explanation:
To distribute, multiply 4 and x which gives you 4x and multiply 4x3 which equals 12 and 12 is positive so the answer is 4x+12.
14 is the answer sorry if I get it wrong :/
To check for continuity at the edges of each piece, you need to consider the limit as
approaches the edges. For example,

has two pieces,
and
, both of which are continuous by themselves on the provided intervals. In order for
to be continuous everywhere, we need to have

By definition of
, we have
, and the limits are


The limits match, so
is continuous.
For the others: Each of the individual pieces of
are continuous functions on their domains, so you just need to check the value of each piece at the edge of each subinterval.