Hey I need help on my math homework...This is supposedly a review problem from last year, but I don't recall ever learning it. So I'm asking for the answers to a couple problems. Thanks! Find Equations for the lines that contain these pairs of points: a.) (0,0) and (2,6). I said the answer was Y= 3x. Am I right? b.) (0,0) and (5,8). I have no clue.. c.) (1,2) and (7,11). No clue again.. If you know how to do these problems I'd be happy to learn how or simply recieve some answers. Thank you.
y2-y1/x2-x1 Theres your slope for each of these. Graph the line to find y intercept. EDIT: first one is right
I have Stats next semester and it took me awhile to remember how to do this stuff. This is not a good sign. a) y = 3x b) y = 1.6x c) y = 1.5x + .5
Do you have a graphing calculator? If so, this would be extremely easy. @Phenomenal: If one of the points is (0,0), then 0 is automatically the y-intercept, or b. Your equation is wrong. Here's some good help on linear equations/graphs.
The easiest formula to remember for a linear function is this: m=(y-y1)/(x-x1) where m is the slope of the line: (y1-y2)/(x1-x2); where y1 is the y-value of one point the line passes through; where x1 is the x-value of that same point that the line passes through. Or, in more complicated terms if you'd like: m=(f(x)-f(a))/(x-a)
isnt it y=x+c X is gradient C is y intercept Thats what we learn in uk. With that i got gradient as 2/6=3 and intercept as 0. So y=3x I think my method is easier
(0,0) and (5,8) take the y(8) and subtract the y(0) step by step: 8-0=8 Than take the x(5) and subtract the x(0) step by step: 5-0=5 Than your slope is 8/5 So your answer is y=8/5x If you need the y intercept(b)than you take one pair of the points so for ex. the ordered pair(5,8) now insert that into the equation y=m(slope)x+b(y intercept) so it would be 8=8/5(5)+b after doing all multiplication in the problem it is now 8=8+b than subtract the 8 from both sides 8-8=8-8+b finally equalling 0=b so in this one your y intercept is 0 so you final answer would be y=8/5x+0 also written as y=8/5x Now you didnt need to figure the y intercept in this one since one of your points was (0,0) but you will eventually need to know how. hope this helps./
You can't use that method for one of the three questions he listed, and generally it's not very helpful anyway. You didn't explain that too clearly. Parentheses imply multiplication.
yeah i know...i mean i did you it implying multiplication in some spots. but i dont really know how to the rest. hows this. if you dont already know these are how the parts of an equation are labled ex. (2,4) the two, or the left number is known as the x The four, or the right number is known as the y in an equation there is also a letter m(this stands for the slope of the line) And there also is the letter b(the y intercept, or the point where the line crosses over the y axes.) (0,0) and (5,8) take the y which is 8 and subtract the y which is 0 step by step: 8-0=8 Than take the x which is 5 and subtract the x which is 0 step by step: 5-0=5 Than your slope is 8/5 So your answer is y=8/5x If you need the y intercept(also known as b)than you take one pair of the points so for ex. the ordered pair(5,8) now insert that into the equation y=mx+b so it would be 8=8/5(5)+b after doing all multiplication in the problem it is now 8=8+b than subtract the 8 from both sides 8-8=8-8+b finally equalling 0=b so in this one your y intercept is 0 so you final answer would be y=8/5x+0 also written as y=8/5x Now you didnt need to figure the y intercept in this one since one of your points was (0,0) but you will eventually need to know how. hope this helps.
Yes, you made it more understandable now. But still, that's making it much more difficult than it needs to be. There are other formulas for linear functions that don't require the y-intercept, just a point through which the line passes.
true true. this is just the first way i was tought, since it is pretty reliable. and it seems like hes doing easy dtuff right now so i was giving him the way that has more steps, but is probably the way the teacher wants him to learn first before he gets into the more complicated but shorter formulas.
wow Thanks. you all helped a lot. Now I can finally finish my homework! This can be closed If need be.
Actually it is dude. Unless you wanted parentases? thats the right way to do it. yours is backwards. If you use yours for the first problem, you get a negative slope. It is posative. Im not really sure what to tell you.