Question

multiply. 3i(3 - 4i) 3i(3 - 4i)=□ (type your answer in the form a + bi. use integers or fractions for any numbers in the expression.)

Explanation:

Step1: Apply distributive property

$3i(3 - 4i)=3i\times3-3i\times4i$

Step2: Calculate each product

$3i\times3 = 9i$ and $3i\times4i=12i^{2}$. Since $i^{2}=- 1$, then $12i^{2}=-12$.

Step3: Combine results

$9i-(-12)=12 + 9i$

Answer:

$12 + 9i$