How do you solve the system of equations 2x + 6y = 3 and - 2x + 14y = 7?

2 Answers
Apr 14, 2018

x=0
y=1/2

Explanation:

2x+6y=3 --- (1)
-2x+14y=7 --- (2)

From (1),
2x+6y=3
2x=3-6y
x=1/2(3-6y) --- (3)

Sub (3) into (2)

-2times1/2(3-6y)+14y=7
6y-3+14y=7
20y=10
y=1/2 --- (4)

Sub (4) into (3)

x=1/2(3-6times1/2)
x=0

Apr 14, 2018

make x in terms of y and then substitute in the second equation

Explanation:

2x + 6y = 3

2x = 3 - 6y

x = 3/2 - 3y

substitute in the second equation

-2x + 14y = 7

-2(3/2 - 3y) + 14 y = 7

-3 + 6y +14y = 7
20y = 10

y = 1/2

then substitute y in any of the 2 equations to get x
you get y = 1/2 and x = 0

Hope this helped