Question

multiply.
-10i·-7i
-10i·-7i =
(simplify your answer. type your answer in the form a + bi.)

Explanation:

Step1: Multiply the coefficients

$(-10) \times (-7) = 70$

Step2: Multiply the imaginary units

$i \times i = i^2$

Step3: Substitute $i^2=-1$

$70 \times i^2 = 70 \times (-1) = -70$

Step4: Write in $a+bi$ form

$-70 + 0i$

Answer:

$-70 + 0i$