9 and 3/8 is 75/8 as a mixed #.
6 buses with 32 students per bus.....6 x 32 = 192 students
each row seats 8 students...192/8 = 24 rows will be needed for all students
<span>
Let's analyze Hannah's work, step-by-step, to see if she made any mistakes. </span>In Step 1, Hannah wrote

<span> as the sum of two separate derivatives </span>

<span>using the </span><span>sum rule.
</span>
This step is perfectly fine. In Step 2,

was kept as it is, and

was rewritten as

using the constant rule.Indeed, according to the constant rule, the derivative of a constant number is equal to zero.
This step is perfectly fine. In Step 3,

was rewritten as

supposedly using the constant multiple rule.
The problem is that according to the constant multiple rule,

should be rewritten as

and not as

.
<span>
Therefore, Hannah made a mistake in this step.</span>
Answer: 
<u>Step-by-step explanation:</u>

NOTE: The sign between 4x and 7 is missing in the question you posted. I assumed it was 4x + 7 in order to solve the equation.
The answer would be 18 because if you put 3a+6a+a=180 (the degrees of a triangle) and solve it a becomes 18