20 minutes = 1/3 of an hour
1/3 = 0.333
1/3 x 45mph = 15, so she drove 15 miles at 45mph
18-15 = 3
3 miles/ 20 mph = 0.15 hours
0.333+0.15 = 0.483 hours total
0.483 x 60 = 28.98 so approximately 29 minutes total driving time
7:15 + 29 minutes is 7:44 am she arrived at work
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Define x :
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Let the dryer be x.
Dryer = x
Washer = x -53
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Construct Equation :
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The washer and the dryer cost $847
⇒ x + x - 53 = 847
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Solve x :
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x + x - 53 = 847
2x - 53 = 847
2x = 847 + 53
2x = 900
x = 450
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Find cost of dryer and washer :
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Dryer = x = $450
Washer = x = 450 - 53 = 397
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Answer: Dryer = $450
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9y+7 + 7y-19 = 180
Y =12 degrees