Expand left side: Expand the left side using the distributive property: (a+2i)(1+bi)=a+abi+2i+2bi2. Since i2=−1, this simplifies to a+abi+2i−2b.
Separate parts: Separate the real and imaginary parts: Real part: a−2b, Imaginary part: abi+2i. Set these equal to the corresponding parts of the right side: a−2b=17 and abi+2=−19.
Solve real part: Solve the real part equation: a−2b=17.
Solve imaginary part: Solve the imaginary part equation: abi+2=−19. Since i is not a real number, we can ignore the i in abi for now and solve for b: ab+2=−19.
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