Am I doing this right? (solving a system using substitution method)?
I'm pretty sure I did something wrong but I don't know what...
is that right?
so it's negative 8.5 then?!
um 2nd answer...how did you get divided by 8?
- TychaBraheLv 71 decade agoFavorite Answer
Why do this the hard way?
x = 7y + 12
2(7y + 12) + 8y = 14
14y + 24 + 8y = 14
22y = -10
y = -5/11
x - 7y = 12
x - 7(-5/11) = 12
x + 35/11 = 12
11x + 35 = 132
11x = 97
x = 97/11
Here's where you made your mistake. You show that 8y = 14 - 2x, but then you substitute that for y in the equation. y = (14 - 2x)/8, and that is what you should substitute.
But since you already have a unit variable (x) in the first equation, use that.
- rinkiewiczLv 44 years ago
you prefer to unravel for between the unknowns in the least confusing equation. utilising p + q = 4, you are able to resolve for q and get q = 4 - p. by using substitution, enter 4 - p in for q in the different equation: 4p + q = a million 4p + 4 - p = a million 3p + 4 = a million 3p = -3 p = -a million Now you have solved for p. you are able to now resolve for q by using putting your fee for p back into between the equations. I"m going to compliment the main elementary one: p + q = 4 -a million + q = 4 q = 5.
- 1 decade ago
You said that 8y=14-2x but then contradicted yourself, because you said x-7(14-2x)=12. here, you said that y=14-2x
then, when you distributed, you said -7 * -2x is -14x, but it is +14x, cuz a negative and a negative is a positive,
after, you said x-14x is 13x but it is -13x.
- Anonymous1 decade ago
the person under me said u did wrong?do u want to correct it?