How do you solve #5x + 8y = 7# and #x + y = 2# using substitution?
2 Answers
Apr 24, 2016
x=3, y= -1
Explanation:
given x+y=2
y= 2 - x (eq. 1)
given 5x+8y=7 (eq.2)
substitute eq. 1 in eq. 2
5x + 8(2-x) =7
5x + 16 - 8x = 7 (open the bracket)
-3x=7-16= -9
x= -9/ -3 = 3
eq 1-
y= 2-3= -1
so x=3, y= -1
Apr 24, 2016
See below for method of solution by substitution.
Explanation:
If
then
and
This would give:
Then, returning to
we have