Bieber896
  • Bieber896
can someone help me on substituting and eliminating systems of equations?! I'm so confused
Mathematics
  • Stacey Warren - Expert brainly.com
Hey! We 've verified this expert answer for you, click below to unlock the details :)
SOLVED
At vero eos et accusamus et iusto odio dignissimos ducimus qui blanditiis praesentium voluptatum deleniti atque corrupti quos dolores et quas molestias excepturi sint occaecati cupiditate non provident, similique sunt in culpa qui officia deserunt mollitia animi, id est laborum et dolorum fuga. Et harum quidem rerum facilis est et expedita distinctio. Nam libero tempore, cum soluta nobis est eligendi optio cumque nihil impedit quo minus id quod maxime placeat facere possimus, omnis voluptas assumenda est, omnis dolor repellendus. Itaque earum rerum hic tenetur a sapiente delectus, ut aut reiciendis voluptatibus maiores alias consequatur aut perferendis doloribus asperiores repellat.
chestercat
  • chestercat
I got my questions answered at brainly.com in under 10 minutes. Go to brainly.com now for free help!
jim_thompson5910
  • jim_thompson5910
Post the full problem please
Bieber896
  • Bieber896
x=3y-8 5y=19+4x
Bieber896
  • Bieber896
@jim_thompson5910

Looking for something else?

Not the answer you are looking for? Search for more explanations.

More answers

jim_thompson5910
  • jim_thompson5910
since x is fully isolated, you can replace the x in the second equation with 3y-8 so `5y=19+4x` turns into `5y=19+4(3y-8)`
jim_thompson5910
  • jim_thompson5910
do you see how to solve for y?
Bieber896
  • Bieber896
5y=19+12y-32??
Bieber896
  • Bieber896
but there's two ys
jim_thompson5910
  • jim_thompson5910
get all the y terms to one side so subtract 12y from both sides to get the y terms to the left side
Bieber896
  • Bieber896
-7y=19+(-32)?
jim_thompson5910
  • jim_thompson5910
good, then combine like terms on the right side
Bieber896
  • Bieber896
-7y=-13
jim_thompson5910
  • jim_thompson5910
what comes next
Bieber896
  • Bieber896
divide both sides by -7?
jim_thompson5910
  • jim_thompson5910
correct
jim_thompson5910
  • jim_thompson5910
\[\Large -7y = -13\] \[\Large \frac{-7y}{-7} = \frac{-13}{-7}\] \[\Large y = \frac{13}{7}\] Notice how the two negatives divide to make a positive result
Bieber896
  • Bieber896
so y=1.85
jim_thompson5910
  • jim_thompson5910
I'd leave it as a fraction because the decimal result is only an approximation
Bieber896
  • Bieber896
oh ok
Bieber896
  • Bieber896
so then do I plug that in to the next equation?
jim_thompson5910
  • jim_thompson5910
yes, you'll plug that into `x=3y-8` to find x
Bieber896
  • Bieber896
so x=-2 3/7
jim_thompson5910
  • jim_thompson5910
or x = -17/7 so the solution as an ordered pair is \(\LARGE \left( -\frac{17}{7}, \frac{13}{7}\right)\)
Bieber896
  • Bieber896
ok thanks so much ! can we just do one more?!
anonymous
  • anonymous
yes
jim_thompson5910
  • jim_thompson5910
sure
Bieber896
  • Bieber896
y=3x+3 y=2x+1
jim_thompson5910
  • jim_thompson5910
y is equal to 3x+3 AND it's also equal to 2x+1
jim_thompson5910
  • jim_thompson5910
since y is equal to those two things, we can set the two equal to each other basically we're performing a substitution
jim_thompson5910
  • jim_thompson5910
y=2x+1 3x+3 = 2x+1 ... replace y with 2x+1 solve for x to get x = ??
Bieber896
  • Bieber896
so do I have to get rid of one of the variables?
anonymous
  • anonymous
isolate your x
jim_thompson5910
  • jim_thompson5910
move the 2x over you do this by subtracting 2x from both sides
anonymous
  • anonymous
x=___
Bieber896
  • Bieber896
1x+3=+1
jim_thompson5910
  • jim_thompson5910
now subtract 3 from both sides to move that 3 to the right side
Bieber896
  • Bieber896
1x=-2
jim_thompson5910
  • jim_thompson5910
which is the same as x = -2
Bieber896
  • Bieber896
yup
Bieber896
  • Bieber896
then plug it in
jim_thompson5910
  • jim_thompson5910
now plug that into either equation to find y
Bieber896
  • Bieber896
so the solution is (-2,3)
Bieber896
  • Bieber896
or -3 lol my bad
jim_thompson5910
  • jim_thompson5910
yes it's (-2,-3)
Bieber896
  • Bieber896
thank you both so much for your help @jim_thompson5910 @tekman1298

Looking for something else?

Not the answer you are looking for? Search for more explanations.