Roxanne is using successive approximation to solve this equation. She started from a graph, where she found the solution to be between and 0. Using the lower and upper bounds from the graph, Roxanne started the first iteration of successive approximation.

Step 1
Rewrite the equation so it equals zero.

Step 2 Evaluate the rewritten equation at the lower and upper bounds.
Since the solution to the equation represents a zero, one bound should yield a negative value and the other should produce a positive value.

Step 3 Take the average of the lower and upper bounds from the graph.

Step 4 Evaluate the rewritten equation at .

Step 5 Since this value is positive, replace the previous lower bound so the bounds are now and .
Where did Roxanne make a mistake, and what was the error?

A.
Roxanne made a mistake in step 2. The actual evaluation of the rewritten equation at is .
B.
Roxanne made a mistake in step 4. The actual evaluation of the rewritten equation is approximately .
C.
Roxanne made a mistake in step 3. The average of the two bounds is .
D.
Roxanne made a mistake at step 5. She should have used as the new upper bound.