Answer:
-4 or 4
Explanation:
We can solve for the value of y by using the first equation to express y in terms of x and then substituting the resulting expression for y into the second equation.
From the first equation, we have:
4x - y = 4
Rearranging this equation to solve for y, we get:
y = 4x - 4
Now, we can substitute this expression for y into the second equation:
2x^2 - y = 4
Replacing y with 4x - 4, we get:
2x^2 - (4x - 4) = 4
Expanding the brackets and simplifying, we get:
2x^2 - 4x + 4 = 4
Subtracting 4 from both sides, we get:
2x^2 - 4x = 0
Factorizing, we get:
2x(x - 2) = 0
Using the zero product property, we see that this equation is satisfied when either 2x = 0 or x - 2 = 0.
If 2x = 0, then x = 0, and we can use the expression for y that we found earlier to get:
y = 4x - 4 = 4(0) - 4 = -4
If x - 2 = 0, then x = 2, and again using the expression for y, we get:
y = 4x - 4 = 4(2) - 4 = 4
Therefore, the possible values of y are -4 and 4. We would need more information to determine which value of y is the correct one in this context.