Solve -5i(-6+5i)

$$- 5 i ( - 6 + 5 i )$$

Evaluate

$$25+30i$$

Solution Steps

Multiply -5i times -6+5i.

$$-5i\left(-6\right)-5\times 5i^{2}$$

By definition, i^{2} is -1.

$$-5i\left(-6\right)-5\times 5\left(-1\right)$$

Do the multiplications. Reorder the terms.

$$25+30i$$

Real Part

$$25$$

Solution Steps

Multiply -5i times -6+5i.

$$Re(-5i\left(-6\right)-5\times 5i^{2})$$

By definition, i^{2} is -1.

$$Re(-5i\left(-6\right)-5\times 5\left(-1\right))$$

Do the multiplications in -5i\left(-6\right)-5\times 5\left(-1\right). Reorder the terms.

$$Re(25+30i)$$

The real part of 25+30i is 25.

$$25$$