Hello,
N is closed for an opération(µ) means that
a,b ∈ N : a µ b ∈N (i suppose so)
Answer (1) ex 2/3 ∉ N
Answer (4) ex 2-3 ∉ N
∀ a,b ∈ N: a+b ∈N is true ; not a answer.
∀ a,b ∈ N: a*b ∈N is true ; not a answer.
Answer:
x = 10
Step-by-step explanation:
1/10(x + 130) = -2(3 - x)
x + 130 = -20(3-x)
x + 130 = -60 + 20x
x - 20x = -60 - 130
-19x = -190
x = 10
Y: x-1 that is the answer. I think so.
the blank is 162
since 81 and 81 are both perfect squares the middle term (blank) will be the product of their roots times 2
√81=9
√81 =9
9 x 9 x 2
= 162
