- Thread starter Dominic
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Substitute 1st in 2nd:Dominic said:I need help.

Determine whether the system has one solution, no solution, or infinitely many solutions:

y=-x+2

3x+3y=6

I'm confused and mad at myself for not knowing how to do this. I hope someone can can me.

3x + 3(-x + 2) = 6

3x - 3x + 6 = 6

6 = 6 ... well?

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If x = 3, is 6=6? Yes

If x = -34, is 6 = 6? Yes

If x = "Purple Cow", is 6 = 6? Yes

It's not really a whole lot less confusing, but I do get some entertainment value out of it.

Sorry, but I have to say it: . Did you even TRY to find the solutions?Determine whether the system has one solution, no solution, or infinitely many solutions:

y = -x + 2

3x + 3y = 6

I'm confused and mad at myself for not knowing how to do this. . . how to do what?

. . Or did you just sit there and say, "They didn't show me the

How do you find out how many solutions a system has? . . . you solve it!

The first equation is already solved for y: . y = -x + 2

Substitute into the second equation: . 3x + 3(-x + 2) .= .6 . . . and solve for x.

We get: . 3x - 3x + 6 .= .6 . ---> . 6 = 6 (?)

We can't solve for x . . . all the x's dropped out.

. . But this is good news: the value of x doesn't matter . . . the statement is true.

So the system is valid for

. . Or did you just sit there and say, "They didn't show me the formula for this!"

Soroban, Confosious once said "man who jumps to conclusions is a man who jumps off cliff". I think it's obvious that if I come here for help its because I tried to find the solution and couldn't! I am not a free loader who expects anyone to do my work for me. If I come to a HELP FORUM it is for that purpose for HELP! If you are willing to help me fine, I appreciate it, but if not keep your unrelated comments to yourself!!

I do appreciate those who have help me. It is the unsoliceted comments the upset me.After all we are here to help each other not belittle one another.

That's your post, Dominic me boy; sure don't look like you tried!Dominic said:I need help.

Determine whether the system has one solution, no solution, or infinitely many solutions:

y=-x+2

3x+3y=6

I'm confused and mad at myself for not knowing how to do this. I hope someone can can me.

You could have least have shown: 3x + 3(-x + 2) =6

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- Apr 12, 2005

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