Answer:
............462........
470
Step-by-step explanation:
Given
z([tex]y^{4}[/tex] - x² ) ← substitute given values
= 2([tex]4^{4}[/tex] - 5² ) ← evaluate contents of parenthesis
= 2(256 - 25)
= 2(235)
= 2 × 235
= 470
