Answer:
We are to find the error made by Sadie and then find the correct simplification.
The error Sadie made is that she wrote
as
instead of
.
The square root of
is
and so she could have further simplified.
The correct simplification is shown below:

Estimated would be 700 x 80
<em>Answer: i=9</em>
<em />
<em>Step-by-step explanation:</em>
<em>-16=-4(-5+i)</em>
<em>-16=20-4i</em>
<em>-20 -20</em>
<em>-36=-4i</em>
<em>Divide by -4 </em>
<em>i=9</em>
It’s either Option 1 or 4