It would be a. because a rectangle has 2 pairs of congruent sides so since the width is 12 and there are 2 sides with that measurement it would be 2(12) and the same goes for the length, and then you add them together.
Yes, that is correct due to the distributive property. It states that you can distribute a number to another number.
for example: a(b + c) = ab + ac
in this case, you are distributing the -1 into the 2x + 10
-1(2x + 10)
(-1) * (2x) + (-1) * (10)
(-2x) + (-10)
-2x - 10
The expression given is ambiguous according to the standard rules of math (PEMDAS) due to the lack of appropriate parentheses and probably the exponentiation symbol ^.
From the context, I assume it to mean
(3^(1/3)) / (3^(1/3)) = 1
Since 3^(1/3) is the cube-root of 3, and is thus irrational.
However, the quotient is exactly 1, which is a rational number.
The example is therefore a counter-example for the statement that "set of irrational numbers is closed under division", or stated differently,
"<span>the set of irrational numbers is not closed under division"</span>
