Answer:
1/5 + 2/5 i sqrt(6) = .2 + .98i
1/5 - 2/5 i sqrt(6) = .2 - .98i
Step-by-step explanation:
5z^2−9z=−7z−5
We need to get all the terms on one side (set the right side equal to zero)
Add 7z to each side
5z^2−9z+7z=−7z+7z−5
5z^2−2z=−5
Add 5 to each side
5z^2−2z+5=−5 +5
5z^2−2z+5=0
This is in the form
az^2 +bz+c = 0 so we can use the quadratic formula
where a = 5 b = -2 and c = 5
-b± sqrt(b^2-4ac)
-------------------------
2a
-(-2)± sqrt((-2)^2-4(5)5)
-------------------------
2(5)
2± sqrt(4-100)
-------------------------
10
2± sqrt(-96)
-------------------------
10
2± sqrt(16)sqrt(-1) sqrt(6)
-------------------------
10
2± 4i sqrt(6)
-------------------------
10
1/5 ± 2/5 i sqrt(6)
Splitting the ±
1/5 + 2/5 i sqrt(6) = .2 + .98i
1/5 - 2/5 i sqrt(6) = .2 - .98i
20 and 8 make a product of 160
and their difference is 12
53:16 and 16:24 for the second part
......................................................
it would be B
