Question 282189: How do I solve for this using substitution.
5x+8y=18
x=6-2y Found 2 solutions by oberobic, Mathematicians:Answer by oberobic(2304) (Show Source):
You can put this solution on YOUR website! Substitution is done by...well...substitution.
You use one equation to find a value for 'x'.
Then you substitute that into the other equation.
.
5x + 8y = 18
x = 6 -2y
.
So the second equation is a easy substitution candidate into the first equation.
.
5(6-2y) +8y = 18
30 -10y +8y = 18
30 -2y = 18
-2y = -12
y = 6
.
Now substitute back to find 'x'.
.
x = 6 -2(y)
x = 6 -2(6)
x = 6 -12
x = -6
.
Check by plugging these values into the other equation to ensure they're right.
.
5x + 8y = 18
5(-6) + 8(6) = 18??
-30 +48 = 18
Correct!
.
Answer:
x = -6
y = 6
.
Done.
You can put this solution on YOUR website! Substitution is pretty cool
Check this out:
and
are you two equations, we know what x is equal, so look at these next two things:
Look in the highlighted area, see how you just replace x with 6 - 2y, we did this because that is what x was equal to in the second equation
distribute combine like terms subtract 30 on both sides divide by -2 on both sides
Time to solve for X
we know y = 6
Your two answers
(
