word problem: i drove 3 hrs decrease speed by 10 mph next 3 hr trip 360 miles what was my speed 1st hr in mph?

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2007-02-18 01:00:19 · 2 answers · asked by brinson 1 in Science & Mathematics ➔ Mathematics

s = 360 miles
t = 3 hr
a = -10 mph (decrease)

use formula
s = ut + 1/2 at^2
360 = u(3) + 1/2 (-10)(3)^2
360 = 3u - 45
speed in 1st hr, u = 135 mph

2007-02-18 02:42:46 · answer #1 · answered by seah 7 · 1⤊ 0⤋

61 the first hr and 41 the second

2007-02-18 09:04:52 · answer #2 · answered by furmanator1957 4 · 0⤊ 0⤋