X+2y=3 Y=2x+14 solve the system by the substitution method

Question

asked Jul 22, 2020 101k views

1 Answer

Joevallender · Answer 1 · 2020-07-26T21:39:03+0000

Answer:

y = 4, x = -5

Explanation:

$x + 2y = 3\\y = 2x + 14\\$

We can solve for x

$x = 3 - 2y\\$

We can then substitute it into the second equation

$y = 2(3-2y) + 14\\y = 6 - 4y + 14\\5y = 20\\y = 4$

y = 4, so we can plug that back into the first equation:

$x + 2(4) = 3\\x + 8 = 3\\x = -5\\$

We can double check:

$4 = 2(-5) + 14\\4 = -10 + 14\\14 = 14\\$

Since it is true, we know it works