Can someone please check this? I fan and give medals! :) Which is an equation in slope-intercept form for the line passing through (5, 1) and (–4, 7). y=2/3x+13/3
@Timelordguy
I don't want to steal Timelordguy's thunder, but to check your answers, just plug in the values 5 and -4 as x into your conjecture (educated answer) and see if the values come out to y = 1 and 7 respectively.
If you need assistance doing that, I am happy to help you.
Yes actually I will need some help doing that. @IParke
So, you believe your equation to be y=2/3x+13/3. To check your answer, plug in the coordinates you were supposed to have the equation fit. So, let's take the first coordinate your equation is supposed to satisfy: (5,1) This coordinate means that when x=5, y=1. Do you follow?
Let's plug those values into your equation and see if the coordinate works.
yes
ok
y=2/3x+13/3 So, for (5,1), this becomes: (1) = (2/3)(5) + (13/3)
Do you follow?
yes I sorta get it
So all I did was replace y with the 1 in (5,1) and the x with 5 in (5,1)
Is this clear?
Since (5,1) means x= 5 and y= 1.
oh ok yes
Good, now please evaluate the right side of your equation that I used substitution on: (1) = (2/3)(5) + (13/3)
Tell me what the right side of the equation ends up being 1 = ?
ok um well I just divide 2 by 3 then multiply by 5 and then add 13 divided by 3?
Correct
7.66666666667
Does 1 = 7.667?
I am sorry to report, your answer is wrong.. BUT! I can give you a nice clue
ok
Make your 2/3's a negative, and try it again :)
ok let me try again
1=1
I absolutely believe you know how to do this problem, you just made an error with the sign somewhere along the way :) You should find that 1=1.
Excellent!
great so it was correct?
Now, for the final test, try using substitution with the other point: (–4, 7)
So to recap, so far you've proven that the equation y=-2/3x+13/3 goes through (5,1). You now need to prove that it also goes through the other point, (-4, 7)
Does this make sense?
um yeah it kinda does
Would you like me to walk you through proving that your equation goes through -4, 7?
yes please your an amazing person!!! God bless you because my math skills are terrible!
haha, God bless you too for trying to improve!
So, we are going to use substitution again.
haha thanks!
So, please plug in the coordinate (-4,7) into the equation: y=-2/3x+13/3
so would it be -4=-2/3(7)=13/3?
Hmmm. Let us remember that the x-coordinate comes first in the coordinate pair :) (x = -4, y = 7)
oh ok duh! so then its 7=-2/3(-4)+13/3
@IParke
Yes! Please evaluate the right side of the equation to see if 7=7!
And if it does, then your equation is perfect :)
Oh my gosh thank you so very much you ARE A LIFESAVER!!!!! :)
Haha, I don't know about that, but I am so happy you're learning. If you are still confused, please let me know, I'll explain all of this to you in plain English.
ok thanks I'll DEFINITELY need your help in the future!
Good luck with your math endeavors!
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