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:
at least four times bigger
Answer:
x = 20 and y = 14.14213562 ( you can simplify it)
Step-by-step explanation
x = the opposite side divided by sin 45 ( the angle)
/ sin(45)
20
y = the opposite side divided by the adjacent side
/ tan(45)
14.14213562
14.14
The vertical angles have equal measures.
Therefore, if ∠ a and ∠b are vertical angles, then m∠a = m∠b.
Answer: m∠b = 115°
Answer:
It is a graph that is not a straight line - it can be described as an equation such as y =mx + c
Step-by-step explanation:
