Because α varies directley to β

(k = constant)
α=7 when β=2
7= 2k
k=
so when α=21
21=

b
b= 6
The real part (-6)
the imaginary part 2i
Answer:
y=4x+9
Step-by-step explanation:
replace m with 4, which is the slope you gave, and
replace b with 9, the y-intercept you gave,
in the equation y=mx+b.
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