Y = ²/₃x + 7
y = ²/₃(5) + 7
y = 3¹/₃ + 7
y = 10¹/₃
(x, y) = (5, 10¹/₃)
The real part of the result is the product of the real parts of the factors and the product of the imaginary parts:
a = 15*6 - (-4)(-3) = 90 -12 = 78
_____
You can treat this the same as any other product of binomials except that i² = -1.
... (15 -4i)(6 -3i) = 15(6 -3i) -4i(6 -3i) = 15·6 -15·3i -4·6i +4·3i²
... = 90 -45i -24i +12i² = (90 -12) -69i = 78 -69i
A
B is incorrect, because some of the campers may have never gone camping before, so they would be unable to say which is their favorite camping spot
C is incorrect because all of those campers have never gone camping before, so they would be unable to say which is their favorite camping spot
D is incorrect because she is asking the campers not the counselors
