Answer:
8 and 32
Step-by-step explanation:
(19)
x³ ÷ 3 - y ( substitute x = 3, y = 1 into the expression )
= 3³ ÷ 3 - 1
= 27 ÷ 3 - 1
= 9 - 1
= 8
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(21)
12k - h² ( substitute h = 2, k = 3 into the expression )
= 12(3) - 2²
= 36 - 4
= 32
