Answer:
-1/10
Step-by-step explanation:
We need to get a common denominator of 10
-1/2 *5/5 = -5/10
2/5*2/2 = 4/10
-5/10 +4/10 = -1/10
Here it is. You can also use the quadratic equation to find the answer.
If you expand out the brackets you get this,
(4+5i)(a+2i) = 4a + (5a)i + 8i - 10
The -10 comes from 5i * 2i.
Squaring i becomes -1.
Let's group the real stuff together,
and imaginary separately,
(4a - 10) + (5a + 8)i
For this to be purely imaginary,
the real part needs to be zero.
Therefore 4a - 10 = 0
Solve for a.
Answer:
PQO and OQP
Step-by-step explanation:
PQO: lines OQ and PQ make the angle.
OQP: Not really sure why it asks for two names. You can probably just flip PQO to OQP and that might work. N is not part of the angle so you can't have an answer with that letter.
Answer:
40
Step-by-step explanation:
