Evaluate
-76+28i
Real Part
-76
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-8\times 9-8i+4i\times 9+4i^{2}
Multiply complex numbers -8+4i and 9+i like you multiply binomials.
-8\times 9-8i+4i\times 9+4\left(-1\right)
By definition, i^{2} is -1.
-72-8i+36i-4
Do the multiplications.
-72-4+\left(-8+36\right)i
Combine the real and imaginary parts.
-76+28i
Do the additions.
Re(-8\times 9-8i+4i\times 9+4i^{2})
Multiply complex numbers -8+4i and 9+i like you multiply binomials.
Re(-8\times 9-8i+4i\times 9+4\left(-1\right))
By definition, i^{2} is -1.
Re(-72-8i+36i-4)
Do the multiplications in -8\times 9-8i+4i\times 9+4\left(-1\right).
Re(-72-4+\left(-8+36\right)i)
Combine the real and imaginary parts in -72-8i+36i-4.
Re(-76+28i)
Do the additions in -72-4+\left(-8+36\right)i.
-76
The real part of -76+28i is -76.
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