Because if you did not you would not have a exact answer.
Y = 40 + 4m
m = minutes
y = total papers graded
<u>ANSWER</u>
The zeros are 
EXPLANATION
Given;
.
We can rewrite the function as



The zeros are found by equating the function to zero.


The multiplicity is 1, since it is odd the graph crosses at this intercept. which is 
Or

The multiplicity is 1, since it is odd the graph crosses at this intercept. which is 
Or

This last root has a multiplicity of 2.
That is
repeats two times.
Since the multiplicity is even, the graph touches the x-axis at the point
.
See graph.
The answer is: "
11 " .
____________________________________________________ → "
x = 11 " .
____________________________________________________Explanation:____________________________________________________Set up the ratio/ proportion as a fraction:
6 cm / 48 cm = 5 cm / (3x + 7) ;
→ The "cm" units cancel out; since: "cm/cm = 1 " ;
→ The "6/48" = "(6 ÷ 6) / (48 ÷ 6) = " 1/8 " ;
→ Rewrite as:

;
Now, we can "cross-multiply" :
__________________________________________________<u>Note</u>: 
;

;
{b

; d

} .
__________________________________________________ As such:
1 * (3x + 7) = 8 * 5 ;
→ 3x + 7 = 40 ;
Subtract "
7" from each side of the equation:
→ 3x + 7 − 7 = 40 <span>− 7 ;
</span>
to get:
→ 3x = 33 ;
Now, divide each side of the equation by "
3" ;
to isolate "x" on one side of the equation; & to solve for "x" ;
→ 3x / 3 = 33 / 3 ;
to get:
____________________________________________________ → "
x = 11 " .
____________________________________________________ →
The answer is: "
11 " .
____________________________________________________