Answer:
y = -10
Step-by-step explanation:
To solve this, you must find the value of x first. To do this you must move the first equation so that x is by itself.
-2x + 3 = 7
Subtract 3 from both sides:
-2x = 4
Divide both sides by -2:
x = -2
Now plug in -2 for x into the second equation, like so:
3x + 1 = 5 + y
3(-2) + 1 = 5 + y
-6 + 1 = 5 + y
Add like terms:
-5 = 5 + y
Subtract 5 from both sides:
-10 = y
