Answer:
18 inches.
Step-by-step explanation:
If the ratio for inches to miles is
,
then you multiply the top and bottom by 6 to get to 30. This gets the numerator to 18 inches.
12. Answer: 2130
<u>Step-by-step explanation:</u>
T = -0.01y + 10.6
9.2 = -0.01y + 10.6
<u>-10.6</u> <u> -10.6 </u>
-1.4 = -0.01y
<u> ÷-0.01</u> <u>÷-0.01 </u>
140 = y
"y" represents the number of years after 1990
1990 + 140
= 2130
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13. Answer: -0.0036° per foot
<u>Step-by-step explanation:</u>
Since the relationship is linear, then we can set up the values as x, y coordinates and use the slope formula to find the rate of degrees over feet.
(6562, 63) and (16405, 28)
rate = 
= 
= 
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14. Answer: $0.28 per kWh
<u>Step-by-step explanation:</u>
Same reason as #13
(200, 55) and (500, 140)
rate = 
= 
= 
Sin2x=2sinxcosx, cos2x=1-2sin^2x
sin(2x)+cos(3x)=2sinxcosx+cos(x+2x)
cos(x+2x)=cosx(1-2sin^2(x))-sinx2sinxcosx
sin(2x)+cos(3x)=2sinxcosx(1-sinx)+cosx(1-2sin^2(x))