By definition we have to:
A set has under an operation if performance of that operation on set members always produces a member of the same set; in this case we also say that the set is closed under the operation.
For this case we have the following polynomials:
Multiplying we have:
The product of two polynomials is also a polynomial.
Answer:
d 
is a polynomial
Biannual and semiannual can be used interchangeably; they both mean “twice a year<span>.” But biennial describes something that occurs every two </span>years<span>.
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Keywords:
<em>equation, operations, equivalent, binomial, square root
</em>
For this case we have an equation in which we must apply operations to rewrite it in an equivalent way. We must start by raising both sides of the equation to the square. Thus, we eliminate the square root of the left side of equality and finally solve the binomial of the right side of equality.
So we have:
By definition:
Thus, 
is equivalent to 
Answer:
Option D
Answer:
3.4 - 2.8d + 2.8d - 1.3 = 2.1
Step-by-step explanation:
The given expression is 3.4 -2.8d + 2.8d -1.3
Let's see the definition of like terms.
Like terms are the terms having the same variable and the same exponents.
Examples: -3xy, 2xy and 4y, 5y and -3, 2.
Now let's identify the like terms from the given expression.
3.4 -2.8d + 2.8d -1.3
Here the like terms are -2.8d, +2.8d and 3.4, -1.3
3.4 -2.8d + 2.8d -1.3
= -2.8d + 2.8d + 3.4 - 1.3 [-2.8d + 2.8d = 0] and 3.4 -1.3 = 2.1
= 0 + 2.1
=2.1
The answer is 2.1
