10/(20-15)=2 hours
20*2=40 miles
15*2+10=40 miles
Glen catch up with Maria after 2 hours at 40 miles
Answer:
n = 9
Step-by-step explanation:
20 + 18 + ... + 6 + 4
---------------------------
a = 20 ; d = -2 ; n = ?
--------
4 = 20 + (n-1)(-2)
-16 = (n-1)(-2)
---------
n-1 = 8
n = 9
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S(9) = (9/2)(20+4)
S(9) = 4.5*24
S(9) = 108
If you meant y = 27x - 3, OK. Then, if x = 4, y = 27(4) - 3, or 108-3 = 105.
