Answer:
1. b ∈ B 2. ∀ a ∈ N; 2a ∈ Z 3. N ⊂ Z ⊂ Q ⊂ R 4. J ≤ J⁻¹ : J ∈ Z⁻
Step-by-step explanation:
1. Let b be the number and B be the set, so mathematically, it is written as
b ∈ B.
2. Let a be an element of natural number N and 2a be an even number. Since 2a is in the set of integers Z, we write
∀ a ∈ N; 2a ∈ Z
3. Let N represent the set of natural numbers, Z represent the set of integers, Q represent the set of rational numbers, and R represent the set of rational numbers.
Since each set is a subset of the latter set, we write
N ⊂ Z ⊂ Q ⊂ R .
4. Let J be the negative integer which is an element if negative integers. Let the set of negative integers be represented by Z⁻. Since J is less than or equal to its inverse, we write
J ≤ J⁻¹ : J ∈ Z⁻
Answer:
y =20
Step-by-step explanation:
you have to get the y by itself so what you do on one side you do to the other. subtract 12 on both sides and you get y=20
This is the isosceles triangle. Therefore, the angles at the base are congruent.
We know that the sum of the measures of the angles in a triangle is 180°.
Therefore we have the equation:

<em>subtract 38 from both sides</em>
<em>divide both sides by 2</em>

<h3>Answer: x = 71.</h3>
Answer: Zero; 9; -18
Step-by-step explanation:
An additive inverse always adds up to zero. 9 is the opposite of -9, and -18 is the opposite of 18