please help

Hello,

Im am completly stuck on some problems, May I please have help, I would be so greatful even if u can just get me at least started.

1)multiple choice: Which line passes through the point (2,-1)?
a)2y-x=0 b)2x-y=0 c)3x-2y=8 d)3x+2y=8

2)Find the unknown coordinate of the point on the line x-2y=8, when x=6.

3)Find the unknow coordinate of the point on the line 3y-1=x,when x=-3.

4)Does (2,-2) pass through the equation 4x+y=10?

5)Does (3,10) pass through the equation y=-2x+4?

Thanks in advance again,
Ryan

1) Plug x = 2, y = -1 into each line equation. Which one "works"? (That is, which one results in a true statement?)

2) Plug "6" in for "x". Solve for "y".

3) Plug "-3" in for "x". Solve for "y".

4) Plug x = 2, y = -2 into the equation. Does it "work"?

5) Plug x = 3, y = 10 into the equation. Does it "work"?

Eliz.

stapel said:

1) Plug x = 2, y = -1 into each line equation. Which one "works"? (That is, which one results in a true statement?)

2) Plug "6" in for "x". Solve for "y".

3) Plug "-3" in for "x". Solve for "y".

4) Plug x = 2, y = -2 into the equation. Does it "work"?

5) Plug x = 3, y = 10 into the equation. Does it "work"?

Eliz.

Click to expand...

1)C is the one that works, thanks for the help.

2)when I solve I get -2y=2, so is that the answer?

3)when i solve I get 3y=2, is this the answer?

4)I get -2=2, is this the answer?, if so wouldnt it be true, yes it does work.

5)I get 6=6 when i solve, is this the answer?

Thanks,
please reply
Ryan

2) Now solve for the value of y.

3) Now solve for the value of y.

4) How do you get that -2 is equal to +2?

5) The question is "is this point on the line?", not "does six equal six?" I told you how to check if the point is on the line. You need to answer "yes" or "no".

Eliz.

you need to divide both sides by the constants to solve for the variables in 2&3

-2y=2 which is true but its not solved for y
it should be y=-1 after you divide both sides by -2

watch your signs on 4&5 your problem is in the arithmitic, and if the statement is true eg: 5=5 then the point is on the line, it satisfies the equation.

Thats what a line is, a collection of points that satisfy the equation. When your calculator plots the line, it just plots all of the points that "work" and the end result is a line.