Evaluate
-116-28i
Real Part
-116
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-12\times 8-12\times \left(5i\right)+4i\times 8+4\times 5i^{2}
Multiply complex numbers -12+4i and 8+5i like you multiply binomials.
-12\times 8-12\times \left(5i\right)+4i\times 8+4\times 5\left(-1\right)
By definition, i^{2} is -1.
-96-60i+32i-20
Do the multiplications.
-96-20+\left(-60+32\right)i
Combine the real and imaginary parts.
-116-28i
Do the additions.
Re(-12\times 8-12\times \left(5i\right)+4i\times 8+4\times 5i^{2})
Multiply complex numbers -12+4i and 8+5i like you multiply binomials.
Re(-12\times 8-12\times \left(5i\right)+4i\times 8+4\times 5\left(-1\right))
By definition, i^{2} is -1.
Re(-96-60i+32i-20)
Do the multiplications in -12\times 8-12\times \left(5i\right)+4i\times 8+4\times 5\left(-1\right).
Re(-96-20+\left(-60+32\right)i)
Combine the real and imaginary parts in -96-60i+32i-20.
Re(-116-28i)
Do the additions in -96-20+\left(-60+32\right)i.
-116
The real part of -116-28i is -116.
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