9514 1404 393
Answer:
107/18
Step-by-step explanation:
Your calculator and/or knowledge of trig function values can help you evaluate this.
= 4/3(1/3) +3/4 -3(3/4) +3(3) -2(1)
= 4/9 +3/4 -9/4 +9 -2
= 107/18
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tan(30°) = 1/√3
tan(45°) = 1
tan(60°) = √3
sin(60°) = cos(30°) = √3/2
The median 13 its in the middle
We start off with 50 as our room temperature.
Then we subtract off 4h to indicate the temperature drops 4 degrees per hour
You can think of it like this
1 hour = drop by 4 degrees
h hours = drop by 4h degrees (multiply both sides by h)
So the expression 50-4h represents the temperature after h hours. We want this to be below 32, so 50-4h < 32 is the inequality we're after
Solving for h leads to
50-4h < 32
-4h < 32-50 ... subtract 50 from both sides
-4h < -18
h > -18/(-4) ... divide both sides by -4; note the inequality sign flips
h > 4.5
If you go beyond 4.5 hours, then the temperature will be below 32 degrees
notes:
- 4.5 hours = 4 hours, 30 minutes = 270 minutes
- the inequality sign flips whenever you divide both sides by a negative number
