Evaluate
-41-23i
Real Part
-41
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7\left(-3\right)+7\times \left(-5i\right)-4i\left(-3\right)-4\left(-5\right)i^{2}
Multiply complex numbers 7-4i and -3-5i like you multiply binomials.
7\left(-3\right)+7\times \left(-5i\right)-4i\left(-3\right)-4\left(-5\right)\left(-1\right)
By definition, i^{2} is -1.
-21-35i+12i-20
Do the multiplications.
-21-20+\left(-35+12\right)i
Combine the real and imaginary parts.
-41-23i
Do the additions.
Re(7\left(-3\right)+7\times \left(-5i\right)-4i\left(-3\right)-4\left(-5\right)i^{2})
Multiply complex numbers 7-4i and -3-5i like you multiply binomials.
Re(7\left(-3\right)+7\times \left(-5i\right)-4i\left(-3\right)-4\left(-5\right)\left(-1\right))
By definition, i^{2} is -1.
Re(-21-35i+12i-20)
Do the multiplications in 7\left(-3\right)+7\times \left(-5i\right)-4i\left(-3\right)-4\left(-5\right)\left(-1\right).
Re(-21-20+\left(-35+12\right)i)
Combine the real and imaginary parts in -21-35i+12i-20.
Re(-41-23i)
Do the additions in -21-20+\left(-35+12\right)i.
-41
The real part of -41-23i is -41.
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