What is the sum of 12 – 5i and –3 + 4i? A. –16 + 63i
B. 9 – i
C. 9 – 9i
D. 15 – 9i

B. 9 - i

Step-by-step explanation:

Combine the real and imaginary parts in numbers 12 - 5i and -3 + 4i

(12 + 5i) + (-3 + 4i)

12 - 3 + (-5 + 4)i

Add 12 to -3. Add -5 to 4.

9 + (-i)

9 - i

step-by-step explanation:

3024 rhe base is what up in worry about

∠1≅∠2 by the alternate exterior angles theorem.

step-by-step explanation:

given, a ∥ b and ∠1 ≅ ∠3 .we have to prove that e ∥ f

we know that ∠1≅∠3 and that a || b because they are given. we see that by the alternate exterior angles theorem. therefore, ∠2≅∠3 by the transitive property. so, we can conclude that e || f by the converse alternate exterior angles theorem.

we have to fill the missing statement.

transitivity property states that if a = b and b = c, then a = c.

now, given ∠1≅∠3 and by transitivity property ∠2≅∠3 .

hence, to apply transitivity property one angle must be common which is not in result after applying this property which is ∠1.

the only options in which ∠1 is present are ∠1 and ∠2, ∠1 and ∠4

∠1 and ∠4 is not possible ∵ after applying transitivity we didn't get ∠4.

hence, the missing statement is ∠1≅∠2.

so, ∠1≅∠2 by the alternate exterior angles theorem.