Answer:
-14
Step-by-step explanation:
I believe you meant 8x−y^2−3. The expression 8x−y2−3 is meaningless.
Letting x take on the vaue -1/4 and y the value 3, we get:
8(-1/4) − (3)^2−3, or
-2 - 9 - 3, or
-2 - 12. Final answer is -14