SOLUTION: Ok, My son came home from school today with Math homework. He is in Algebra 1 and they have requested he have a TI-83. I intend to buy this for him but I haven't yet and he has hom

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Question 94994: Ok, My son came home from school today with Math homework. He is in Algebra 1 and they have requested he have a TI-83. I intend to buy this for him but I haven't yet and he has homework tonight. The teacher only explained how to do the problem on the calulator not on paper. I know it can be done on paper but I really do not remember how to do it. I looked in his math book and the book only goes to Chapter 12 and the worksheet is for Chapter 13. I can't figure out how to solve these problems and I'm hoping for some help. He only has to do certain problems so I'm going to send you one of the ones he doesn't have to do.
The question reads as follows:
Solve ecah equation if the domain is {-2, -1, 1, 3, 4}.
The question is as follows:
y=4 - 5x
If you could just show me how to work these I can help him with the ones he has to turn in tomorrow.
Thank you.
Found 3 solutions by Earlsdon, scott8148, samuenkadi:
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Ok, you can start by recalling that the "domain" of a function is the set of all possible values of the independent variable.
In your function y+=+4-5x x is the independent variable (y is the dependent variable).
So you can answer the problem by assigning to x in your function, each of the given values of the domain, then solve for the corresponding value of y.
y+=+4-5x Let x = -2 The first of the given values in the domain.
y+=+4-5%28-2%29
y+=+4-%28-10%29
y+=+4%2B10
y+=+14 This is the value of y that corresponds to the domain value of -2.
Now you repeat this process for each of the remaining given values of the domain.
y+=+4-5x Let x = -1 The second value in the set.
y+=+4-5%28-1%29
y+=+4-%28-5%29
y+=+4%2B5
y+=+9
y+=+4-5x Let x = 1 The third value.
y+=+4-5%281%29
y+=+4-5
y+=+-1
You proceed in this fashion until you have used all five values of the given set.
y+=+4-5x Let x = 3.
y+=+4-5%283%29
y+=+4-15
y+=+-11
You should be able to finish these.

Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
the domain is the set of x values ... the range is the solution set of y values which is found by plugging the x values into the equation

y=4-5(-2)=14 ... y=4-5(-1)=9 ... y=4-5(1)=-1 etc.

the range (solution set) is {14, 9, -1, -11, -16}

Answer by samuenkadi(3) About Me  (Show Source):
You can put this solution on YOUR website!

x -2 -1 1 3 4
4 4 4 4 4 4
-5x 10 5 -5 -15-20
y 14 9 -1 -11-16