# Thread: final exam help >.<

1. ## final exam help >.<

i dont understand ---real numbers--- a question is ''name the set or sets of numbers to which the real number belongs'' -75/22

and i dont understand ----''solve the equation then check your solution''
4=-4(d+9) if a=/-2,4,9,0,6,3,1,2,-4/ b=/4,7,20,-8,2,15,12,-5,17/ c=/27,65,37,18,74,14/
d=/-18,-48,-52,12,-36,36/
and the next problem is d-c

another this i dont understand is what the diffrence between odds and probability like that 2:1 or 1/3 chances

this is one i dont get ''write a direct variable equation that relates x and y. assume that y varies directly as x. then solve.'' If y=-25 x=-5, find y when x=9

what is a parrallel box-and-whiskers plot

i would really really apreciate if anyone would help, my exam is coming and i understand most of everything else. please help

2. Originally Posted by dipstik05
''name the set or sets of numbers to which the real number belongs'' -75/22
Unless I'm misunderstanding the question, it belongs to:
real numbers
rational numbers

3. Originally Posted by dipstik05
''solve the equation then check your solution''
4=-4(d+9) if a=/-2,4,9,0,6,3,1,2,-4/ b=/4,7,20,-8,2,15,12,-5,17/ c=/27,65,37,18,74,14/
d=/-18,-48,-52,12,-36,36/
and the next problem is d-c
check to see if you wrote this problem correctly. As it's written, I don't think it has a solution.

4. Originally Posted by dipstik05
''write a direct variable equation that relates x and y. assume that y varies directly as x. then solve.'' If y=-25 x=-5, find y when x=9
If x varies directly with y, then we can say:
x = K*y

Since we know y = -25 when x = -5, we can solve for K:
-5 = K*(-25)
K = 1/5

Now, the relationship between x and y becomes:
x = 1/5*y

To find y when x = 9, we plug in 9 and solve for y:
9 = 1/5*y
y = 45

5. Originally Posted by ecMathGeek
If x varies directly with y, then we can say:
x = K*y

Since we know y = -25 when x = -5, we can solve for K:
-5 = K*(-25)
K = 1/5

Now, the relationship between x and y becomes:
x = 1/5*y

To find y when x = 9, we plug in 9 and solve for y:
9 = 1/5*y
y = 45
thank you this helped me the most .. , but i dont understand rational numbers still how do u get that answer...

6. Originally Posted by dipstik05
thank you this helped me the most .. , but i dont understand rational numbers still how do u get that answer...
You have to understand how rational numbers are defined.

A rational number is any number that can be written as a quotient (a fraction) with an integer numerator and a non-zero integer denominator. In other words, if I delcare that n is a rational number then I can write n as:

n = q/p

where q and p are integers and p does not equal 0.

Alternatively, a rational number is any number that has a terminating or repeating decimal. An example of a terminating decimal is 1.325 because the decimal stops at 5. An example of a repeating decimal is 6.66666... (where the 6's go on forever). Numbers like 103 and 3546987929.1 are also examples of terminating decimals. IF the number is NOT a terminating or repeating decimal number, THEN the number is NOT a rational number.

Example: The number n = 1.2 is a rational number because it's a terminating decimal. Also 1.2 = 12/10, which is a fraction that contains only integers in the numerator and denominator.

Example: The number n = 3 is a rational number because it is a terminating decimal. Also 3 = 3/1 which is a fraction with integers on the numerator and denominator.

Example: The number n = 3.333333333.... (the 3's go on forever) is a rational number because it is a repeating decimal. Also it CAN be written as a fraction: 3.33333... = 10/3 , with an integer numerator and denominator.

Example: The number n = sqrt(2) is NOT a rational number. (NOTE: the "sqrt" means "square root" which is a function that asks the question: what number times itself equals this number. The sqrt(4) is 2 because 2 times itself equals 4). The sqrt(2) cannot be written as a fraction and it is a number that has a decimal which never repeats or terminates.

Notice that in your problem, the number is already written as a fraction: - 75/22. By the definition, this MUST be a rational number because its a fraction with integers in the numberator and denominator.

7. Originally Posted by ecMathGeek
You have to understand how rational numbers are defined.

A rational number is any number that can be written as a quotient (a fraction) with an integer numerator and a non-zero integer denominator. In other words, if I delcare that n is a rational number then I can write n as:

n = q/p

where q and p are integers and p does not equal 0.

Alternatively, a rational number is any number that has a terminating or repeating decimal. An example of a terminating decimal is 1.325 because the decimal stops at 5. An example of a repeating decimal is 6.66666... (where the 6's go on forever). Numbers like 103 and 3546987929.1 are also examples of terminating decimals. IF the number is NOT a terminating or repeating decimal number, THEN the number is NOT a rational number.

Example: The number n = 1.2 is a rational number because it's a terminating decimal. Also 1.2 = 12/10, which is a fraction that contains only integers in the numerator and denominator.

Example: The number n = 3 is a rational number because it is a terminating decimal. Also 3 = 3/1 which is a fraction with integers on the numerator and denominator.

Example: The number n = 3.333333333.... (the 3's go on forever) is a rational number because it is a repeating decimal. Also it CAN be written as a fraction: 3.33333... = 10/3 , with an integer numerator and denominator.

Example: The number n = sqrt(2) is NOT a rational number. (NOTE: the "sqrt" means "square root" which is a function that asks the question: what number times itself equals this number. The sqrt(4) is 2 because 2 times itself equals 4). The sqrt(2) cannot be written as a fraction and it is a number that has a decimal which never repeats or terminates.

Notice that in your problem, the number is already written as a fraction: - 75/22. By the definition, this MUST be a rational number because its a fraction with integers in the numberator and denominator.
thanks i understand now , last thing .. how can i use the quadratic formulas to factor ,,,,,,i dont get slope intercept i got most of the concepts of slope intercept but likehow do u write a equation in standard form and example like this ''find the line that passes through each point with the given slope.'' (1,-2) m=4 how do u solve somthing like this