Aos= -b/2a so plunin your numbers and you'll get the AOS so you can find the vertex
N*(21/100)=(700/100)
n=(700/100)/(21/100)
n=(700/100)*(100/21)
n=700/21
n=33+1/3
So <em><u>thirty three</u></em> $0.21 pencils can be purchased for $7.00.
Sandra hikes 9/10 mile every 30 minutes, or 1/2 hour.
How many miles does she hike each hour?
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9/10 miles per 30 minutes
for example 9/ 10 per 30 minutes
It means that in an hour it will be twice 30 minutes
(9/10) * 2 = 18/10
= 9 / 5
= 5/5 +4/5
= 1 4/5
