How do you solve the system $x − 2y = 14$ and $x + 3y = 9$ by substitution?

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Answer 1 · 2015-05-24T17:04:06

Replace one of the variables in one of the expressions with its value from the other expression and then solve.

x - 2y = 14 means that x = 14 + 2y
x + 3y = 9 means that (14 +2y) + 3y = 9
5y = 9 - 14 = -5
y = -1
x = 14 +2y = 14 - 2 = 12

How do you solve the system x − 2y = 14x − 2y = 14 and x + 3y = 9 x + 3y = 9 by substitution?