calculating each of the products
noting that i² = (√- 1 )² = - 1
(1 + 2i)(8i) ( distribute by 8i )
= 8i + 16i² = - 16 + 8i ← complex number
(1 + 2i)(2 - 5i) ( expand using FOIL )
= 2 - 5i + 4i - 10i²
= 2 - i + 10 = 12 - i ← complex number
(1 + 2i)(1 - 2i) ( expand using FOIL )
= 1 - 2i + 2i - 4i²
= 1 + 4 = 5 ← real number
(1 + 2i)(4i) ( distribute by 4i )
= 4i +8i² = - 8 + 4i ← complex number
(1 + 2i)(1 - 2i) is the only product which results in a real number
The perimeter of MATH is 4w + 6 and the perimeter of GEOM is 6w - 8. the perimeters are the same so set them equal,
4w + 6 = 6w - 8... use inverse to get all like terms on opposite sides
-4w + 8 = -4w + 8
14 = 2w... divide both side by 2 to get w alone
÷2 = ÷2
7 = w
so B. 7 is the answer
5/7, I don't know what that is as a decimal, but I hope it helps
Answer:
-5 ÷ 4 = -1.25 or 1 
The answer is -1.25
I hope that this helps you! ^‿^
