4b²+20b+25=0
Divide everything by 4
b²+5b+ 6.25=0
use the quadratic formula
x= (-b+ or - √b²-4ac) /2a
x= (-5 + or - √5²-4*1*6.25) /2(1)
x= -5/2 so
in this case, b= -5/2
Answer:
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Step-by-step explanation:
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2 1/4 miles => 1 week
1 mile => 1 ÷ 9/4
( 9/4 is an improper fraction of 2 1/4 )
12 1/2 miles => ( 1 ÷ 9/4 ) × 25/2
= 50/9
= 5 5/9 weeks
( 25/2 is an improper fraction of 12 1/2 )
Therefore, it will take 5 5/9 weeks for the company to replace the stretch of road.
( you can round it off to 6 weeks if the qn specify to give to the nearest whole number )