Help with math please?

Question

Could someone check 2 and 3 to see if they are correct, question 1 i don't understand, can someone tell me how to do it so i can get the answer myself?

1. Find the prime factorization of 15.

2.Use your calculator to evaluate the following expression if x = 5.32, and y = –5.86, and z = –4.11. Round your answer to the nearest tenth.
x – yz
A) –17.7
B) –20.2
C) –18.8 Correct?
D) –20.1


3.Which property of the real numbers is illustrated by the following statement?
(16 + 0) + 7 = 16 + (0 + 7)
A) Commutative property of addition correct?
B) Associative property of addition
C) Distributive property

Answer 1

1. Prime factorization is reducing the problem to only prime numbers. 15 is easy in that it is 3 x 5.

2. Yes, C is correct.


3. associative property (http://hotmath.com/hotmath_help/algebra1/properties_of_addition.html)

Answer 2

1.) I always tutor math. Prime factorization is breaking down a number to find the prime #'s that it's comprised(made up )of.
You can use a tree diagram to help.
15-5 15 breaks into 5 and 3 which are both prime #'s
l (numbers that can only be divided by themselves
3 and 1.) This is the answer or prime factorization of
15. You can check by multiplying the final 2 prime #'s together to equal the beginning number. 5x3=15 so it's correct.

2.)This question gives you the values of x,y, and z so you just do the equation. It says what is X(5.32)- Y x Z (since y and z are together you multiply.)You multiply first as the rules of BEDMAS say (M is before S meaning you multiply before you subtract.) Y x Z = -5.86 x -4.11=24.0846(It's positive through integer operations.) Now it's X - 24.0846 or 5.32- 24.0846= -18.7646. Since you round to the nearest tenth, the tenth is the first # after the decimal which in this case, .7646 is closest to 8 since it's .76 and 6 is ABOVE middle in 1-10 or tenth so you go UP. Now it is -18.8 or answer C.) so you're correct.(It's negative because you subtracted a larger # from a smaller-it's how it works.)

3.) This is easy. You just have to know the definitions of Commutative, Associative, and Distributive toward a binary math sequence(math sequence with multiple operations where order of operations must occur by using Bedmas.)
Commutative: Having the property that one term operating on a second is equal to the second operating on the first, as a × b = b × a.

Associative: Giving an equivalent expression when elements are grouped without change of order, as (a + b) + c = a + (b + c).

Distributive: Having the property that terms in an expression may be expanded in a particular way to form an equivalent expression, as a(b + c) = ab + ac.

Now, whichever definition matches what is shown in the equation in the question, that is correct so...Associative matches perfectly when you substitute the variables in the definition for the #'s used in the equation in the question. So, no, A is close but not correct since the commutative definition doesn't match so it's B- the associative property of addition which is displayed in the definition and matches exactly the question. I hope I helped after all this time and hope and you now know how to do it. Remember to do everything you can to solve a question even if it could be as simple as a definition. Your welcome!!I t's easy. I'm grade 8 and I'm not a nerd but I'm smart!! If you still have problems understanding my clear explanation, post more questions or use a dictionary. Sorry it costs points but I'm here and good luck. I really need best answer!!!!!

Answer 3

1. prime factors are the prime numbers
that multiply together to make that number "15"
in this case
15 = 3*5
(other examples:
20 = 2 * 2 * 5, or 2^2 * 5 using exponents
100 = 2*2*5*5, or 2^2 * 5^2 using exponents)

2."evaluate" means to plug in the given values for
x, y, z
into the expression
x - y*z
and write what you get
in this case
(5.32) - (-5.86)(-4.11)
- 18.7646 rounds to - 18.8
So C is correct

3. The associative property means the parentheses
are changed but the values stay in the same position.
so B is the right answer, not A
Commutative is trading the position of the numbers such as
a + b = b + a for addition
a * b = b * a for multiplication

Answer 4

In the first problem systematically go through the primes start from the lowest you know. With any problem you rarely have to go above 11, but you do sometimes. Example does 2 (the lowest prime go into 15? No.
Does 3? Yes, so it is one of the primes in your factorization. Continue. When you are done all the numbers should multiply out to the original and each one should be primes.

Let's try a different one... 24
Does 2 go into 24? yes, 12 times. Start again. Does 2 go into 12? Yes 6 times. Again, does 2 go into 6? Yes, 3 times. Does anything go into 3? No it is a prime so you are done.

The prime factorization of 24 is then 2, 2, 2, 3. You see they are all primes and 2*2*2*3=24

Your #2 is correct

Your #3 is correct

Answer 5

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