Questions on Algebra: Functions, Domain, NOT graphing answered by real tutors!

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Question 21859: How do you tell if a table or if a graph represents a function?
Well, LET THE TABLE OR GRAPH SHOW X AND Y...WE SHALL SEE HOW OR WHEN WE SAY Y=F(X).LET THE VALUES OF X AND Y BE AS SHOWN BELOW
X....A.....B......C......D......E
Y....P.....Q......Q......R......S.....T....U....V
SOME TIMES THEY ARE SHOWN AS ORDERED PAIRS (A,P),(B,Q),(C,Q),(D,R),(E,S).UNRELATED ELEMENTS LIKE T,U,V ARE LEFT ALONE.
TWO QUESTIONS SHOULD BE ANSWERED WITH YES IF WE WERE TO CALL Y=F(X)...
Q.1. IS EVERY ELEMENT OR VALUE UNDER X HAVE A CORRESPONDING ELEMENT OR VALUE UNDER Y..........WE FIND IT IS SO IN THIS CASE ...SO YES.NOTE THAT EVERY ELEMENT IN X SHOULD HAVE A CORRESPONDING ELEMENT(CALLED IMAGE) IN Y ,FOR Y=F(X),BUT NOT NECESSARILY THE OTHERWAY ROUND..WE FIND HERE THAT T,U,V IN Y ARE NOT ASSOCIATED WITH ANY ELEMENT IN X.THAT IS O.K.BUT SUPPOSE THERE IS ONE ELEMENT SAY F IN X WHICH IS NOT ASSOCIATED WITH ANY ELEMENT IN Y THEN IT IS NOT A FUNCTION.
Q.2.ONE ELEMENT IN X CANNOT HAVE MORE THAN ONE IMAGE IN Y.WE FIND IT TO BE SO IN THIS CASE SO YES...NOTE AGAIN HERE 2 ELEMENTS IN A CAN HAVE SAME IMAGE IN Y AS IN THIS CASE BOTH B AND C HAVE SAME IMAGE Q...THAT IS O.K. BUT NOT THE OTHERWAY ROUND...THAT IS A CANNOT HAVE P AND ANOTHER SAY T AS ITS IMAGE..THAT IS IMAGE OF EVERY ELEMENT IN X SHALL BE UNIQUE.
THAT IS ALL IF THESE 2 QUESTIONS ARE ANSWERED IN YES THEN Y=F(X), does that help you understand better?

Click here to see answer by venugopalramana(3286)

Question 23028: Find the domain of the rational expression.
(3x-1)/(x^2+3x)
Click here to see answer by stanbon!(97)

Question 22489: I need to rewrite the equation so that y is a fuction of x:
-2x+5y-6=-11
6+-2x+5y-6=-11+6
1/2x*-2x+5y=-5*1/2x
This is as far as I got, please help.
Click here to see answer by rapaljer(4671)

Question 22071: With this problem, I need to find the function and state the domain of each given the following functions f and g.
a) (f+g)(x) b) (f-g)(x) c) (f*g)(x) d) (f/g)(x)
Problem:
f(x)=1+1/x; g(x)=1/x
I don't understand how to do this function with the letter "d", I already got "a", "b" and "c".
Can you please help?
Click here to see answer by venugopalramana(3286)

Question 21813: IF A CUSTOMER PAYS WITH A $100 BILL, THE CHANGE IS DEPENDENT ON HOW MANY CD'S ARE BEING PURCHASED. WRITE A FUNCION RULE TO SHOW HOW MANY CHANGE IS GIVEN IF EACH CD COSTS $9.
Click here to see answer by rapaljer(4671)

Question 23177: I am having a hard time with this question. could somebody PLEASE!!!!!!
HELP ME.
Find the value of s if the perimeter of the square is 36 inches

this is the square
____________ (s+4)

____________

Click here to see answer by Paul(988)

Question 23212: My homework says "Write each equation in standard form using integers". I don't know how to do that! Please help me. One of the problems are y=-.5x-.5 Please help me!
Click here to see answer by rapaljer(4671)

Question 21878: You are traveling by car and leave home at 8:00 A.M.,you are 36 miles from home. Find the average speed in miles per hour.
Click here to see answer by rapaljer(4671)

Question 20904: Four equations are shown. Which lines are parallel? Which lines are perpendicular?
a. y=-1/8x+2
b. y=8x+4
c. y=-8x+2
d. 8x+y=4
Fill in the blanks with the correct leters.
Lines______ and ______ are parallel.
Lines______ and ______ are perpendicular.
Click here to see answer by venugopalramana(3286)

Question 23348: 1.y=x^2+3
2.3-4x=y
Find domain and range of both one and two
Click here to see answer by stanbon(75887)

Question 23456: A teacher wishes to schedule a quiz or exam during part of a two-hour class.The equation 1+e=120 can be used to find the available lecture time "1" given that "e" minutes are planned for the quiz or exam.Determine the ordered pairs that satisfy the equation if the domain is{20,30,45,60}.
Click here to see answer by venugopalramana(3286)

Question 23677: how do you indentify the domain and range
Click here to see answer by rapaljer(4671)

Question 23643: Can you please help me find out how to do this problem!
If g(x)=x^2-4x+1 find the value if: -2g(3)
Click here to see answer by rapaljer(4671)

Question 23841: Choose the correct range for the function y = 250 + 10x where 0 <= x <= 4 and x is an integer.
Click here to see answer by ilana(307)

Question 23955: how do you know whether a problem is a function or not??
Click here to see answer by rapaljer(4671)

Question 23989: How do you solve this 2f(5)=_________ if fx=3x+4????? thank you
Click here to see answer by rapaljer(4671)

Question 24022: Please help me solve this question!!
The width of a rectangle measures W. The lenght of the rectangle measures 12 units more than the width. The area of the rectangle is W(W + 12). What is a reasonable domain for the lenght of this rectangle.
A. W > 0
B. W < 12
C. W > 12
D. W = 12
if you could help me with this it would mean a lot to me!! thanks!!!
Click here to see answer by venugopalramana(3286)

Question 24018: i dont understand how to solve the problems.
for example:
-2x + 4y = 0
PLEASE HELP!
Click here to see answer by longjonsilver(2297)

Question 24006: i wanna know the answer to
(2a^4)(3a^5)
thanks
Click here to see answer by longjonsilver(2297)

Question 24002: would you please help me?? what is 1/2g(6)=________ if g(x)=-x squared??? thank you
Click here to see answer by longjonsilver(2297)

Question 24330: x-(4-x)
Click here to see answer by AnlytcPhil(1806)

Question 24387: I need a refresher on finding range & domain please!
f(x)= 1+x^2
What is the range & domain?
Click here to see answer by AnlytcPhil(1806)

Question 24562: Given that g(x)=3x^2-2x+1, find each of the following:
g(0)
g(3)
g(1-t)
g(-1)
g(-x)
I haven't been in Algebra in 13 years. The teacher suggested that I go back to basic, but I am determined to pass this class. I appreciate any help you can provide.
Click here to see answer by Earlsdon(6294)

Question 24607: i DO NOT UNDERSTAND HOW TO DO THIS PROBLEM
X-2<1
-
3
Click here to see answer by elima(1433)

Question 24659: Please help me solve this problem

Factor 4x⁴ - y²

Click here to see answer by AnlytcPhil(1806)

Question 24795: what does functions, domain and not gragphing means....??? i am having a test on the exam and i forgot all my algebras because now i am in geometry now..... what does it mean and give me a couple of examples for me to study before the coming test...???? thank you for your help.....
diane vang
Click here to see answer by elima(1433)

Question 24863: please solve:
if f(x)=2x^+1/2x-4, what is f(-1/2)?
Click here to see answer by rapaljer(4671)

Question 24913: find the indicated value of f(x)
f(x)= -x2-4x+3
Click here to see answer by xxfuncrazychicxx(2)

Question 24993: f(x)=(2x+1)/(3x-5)
Find f(x+h)
HELP!!!!
Click here to see answer by josmiceli(19441)

Question 25126: Let f:X to Y and g:Y to W such that g.f is injective.
a) Show f is injective.
b) Give an example of functions f and g for which g.f is injective but g is not injective.
Click here to see answer by khwang(438)

Question 25398: When x = 1 and y = - 2 find the value of 7x - 4y
Click here to see answer by longjonsilver(2297)

Question 25425: Can you please show me the surface area of a box as a function of length, width, and height.
Click here to see answer by Earlsdon(6294)

Question 25427: For the function f = {(2,5), (3,9), (-1,11), (5,3)}, find f(2).
Click here to see answer by AnlytcPhil(1806)

Question 25494: Paul earns $4 an hour working at the librabry and $8 an hour mowing lawns. This week he worked 25 hours and earned $164. How many hours did he work at the librabry.
Click here to see answer by Paul(988)

Question 25630: the perimeter of a triangle measures 62cm. the 2nd side is 2 times longer than the fist, and the 3rd side is 12cm larger than the second. What is the length of the longest side.
Click here to see answer by Paul(988)

Question 25700: Let f(x)=2x^2-4x+1 and g(x)=3x+2, evaluate the following.
f[g(1)] The answer in the back of the book says 31. How do they get that answer?
Click here to see answer by Paul(988)

Question 25618: the perimeter of a triangle measures 62cm. the 2nd side is 2 times longer than the fist, and the 3rd side is 12cm larger than the second. What is the length of the longest side.
Click here to see answer by pwac(253)

Question 25811: We are Simplifying Exponential Functions and there is this problem that I just don't understand. Please help me solve this equation: . Thank you so much!
Click here to see answer by atif.muhammad(135)

Question 26112: I was not sure which catagory to submit this question under. So here goes.
When dealing with integers in word problems, I do not understand what is fully meant by even or odd consecutive integers. For example, it might say add three odd (or even) consecutive integers. To me, odd infer 1,3,5,7... even infers 0,2,4,6... So, X plus the next consecutive odd integers is??! do you understand my question, and can you steer me straight.
Thank you! Drew Lurie
Click here to see answer by mathrebel(25)

Question 26362: How do you do piecewise defined functions??
Click here to see answer by uknouluvme89(30)

Question 26373: f(x)=-6x-19. Thank you so much for your help. I have another one too, f(x)=10x/(16x+4). I am so grateful for your help.
Click here to see answer by stanbon(75887)

Question 26456: -2(x + 3y)=18
Click here to see answer by Alwayscheerful(414)

Question 26455: -2(x=3y)=18
Click here to see answer by Alwayscheerful(414)

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