We can multiply the number of parts Marsha has finished by the miles of each part:
5 × 1/10
= 5/10
=1/2
Therefore, she raced 1/2 miles.
Hope it helps!
Answer:
Step-by-step explanation:
Remark
I don't think you need the quadratic formula for this equation. It just factors into (b - 2)(b - 2), but I'll do it because you requested it.
Formula

Givens
a = 1
b = - 4
c = 4
Solution
x = - - 4 +/- sqrt((-4^2) - 4*1*4)
====================
2*1
x = 4 +/- sqrt (16 - 16)
==========
2
x = 4/2
x = 2
There are 2 roots but both of them are the same. Some teachers say there is only 1 root. I'm in that group.
If you draw the line and mark -2 and 3 you find that they are 5 apart. By calculation, subtract the lowest from the highest: 3 - -2 = 3+2 = 5