Given that x + y = 7 and 3x-y = 5, evaluate \(\frac{y}{2}-3\).
Answer Details
To solve this problem, we first need to find the values of x and y, and then substitute them into the expression \(\frac{y}{2}-3\).
From the given equations, we can use the elimination method to solve for x and y. Multiplying the second equation by 2 and adding it to the first equation, we get:
2(3x-y) + (x+y) = 11x = 17
x = 17/11
Substituting x into the first equation, we get:
y = 7 - x = 7 - 17/11 = 60/11
Now we can substitute these values into the expression \(\frac{y}{2}-3\):
\(\frac{y}{2}-3 = \frac{60/11}{2} - 3 = \frac{30}{11} - \frac{33}{11} = -\frac{3}{11}\)
Therefore, the answer is -1.