SOLUTION: 5x-6y=-6 5x+51=y 5x-6(5x+51)=-6 5x-30x+306=-6 25x-300 x=-12, and y=5x+51 =-56+51 = my answer was -5 but, real answer is -9... Can you please help me understand this? T

Question 201869: 5x-6y=-6
5x+51=y
5x-6(5x+51)=-6
5x-30x+306=-6
25x-300
x=-12,
and
y=5x+51
=-56+51
= my answer was -5 but, real answer is -9...
Can you please help me understand this?
Thank you so much!!!!

Found 2 solutions by rfer, PRMath:
Answer by rfer(16322) (Show Source): You can put this solution on YOUR website!
I agree with everything you did down to x=-12
then I pluged -12 into one of the original equations.
5x-6y=-6
5*-12-6y=-6
-60-6y=-6
-6y=60-6
6y=-54
y=-9
Answer by PRMath(133) (Show Source): You can put this solution on YOUR website!
5x-6y=-6
5x+51=y
5x-6(5x+51)=-6
5x-30x+306=-6
25x-300
x=-12,
Ok, all of the above is correct! :-) Good for you. Now you need to "plug" the -12 into your equation and that's where you made your mistake......
you had......

y=5x+51 <------this is correct.....

=-56+51 <------this is not correct. It should be:
y = 5(-12) + 51 (See where I "plugged" in the -12 for the "x" variable?
SOOOO now you solve:
y= 5(-12) +51
y= -60 + 51 (5 times -12 equals -60)
y= - 9 (-60 + 51 gives you -9)

Did that help? I hope so!
:-)

RELATED QUESTIONS
I'm having trouble with System of Linear Equations by Substitution. One of the problems (answered by jim_thompson5910)
5x^2+30x+24y=51 (answered by greenestamps)
5x^2+1=51 (answered by palanisamy)
5x+16=51 (answered by Alan3354)
6(5x+2)=30x+12 (answered by richwmiller)
-5x+3y=51 y=10x-8 x=?... (answered by TimothyLamb)
5x-4=25x-6 (answered by Maths68)
Select the set of equations that represents the following situation: the sum of two... (answered by mananth)
5x + 3y = -9 5x - 3y = -51 give the ordered pair as solution I got an answer as -9/5... (answered by Edwin McCravy,scott8148)