SOLUTION: how do you solve this equation: y=2x-5 y=6x+7 i don't understand how to do this and i haven't looked at one of these problems in a LONG time!

Algebra ->  Systems-of-equations -> SOLUTION: how do you solve this equation: y=2x-5 y=6x+7 i don't understand how to do this and i haven't looked at one of these problems in a LONG time!      Log On


   



Question 152273: how do you solve this equation:
y=2x-5
y=6x+7
i don't understand how to do this and i haven't looked at one of these problems in a LONG time!

Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
how do you solve this equation:
y=2x-5
y=6x+7
:
If both expressions = y then:
6x + 7 = 2x - 5
:
Subtract 2x from both sides:
6x - 2x + 7 = -5
:
Subtract 7 from both sides
4x = - 5 - 7
4x = -12
:
Divide both sides by 5
x = %28-12%29%2F4
x = -3
:
Find y using the 1st equation, substitute -3 for x
y = 2(-3) - 5
y = -6 - 5
y = -11
:
Check solution in the 2nd equation:
6(-3) + 7 =
-18 + 7 = -11 (which is y)