Answer:
9240 feet
Step-by-step explanation:
Petrov ran 7 laps around a track.Each lap around the track is a distance of 1/4 mile.
Step 1
The total distance Petrov ran in miles is calculated as:
1 lap = 1/4 mile
7 laps = x mile
Cross Multiply
x = 7 × 1/4 mile
x = 1.75 miles
Step 2
What is the total distance Petrov ran in feet?
1 mile = 5280 feet
1.75 miles = x
Cross Multiply
x = 1.75 × 5280 feet
x = 9240 feet
Therefore, the total distance Petrov ran in feet is 9240 feet
-2x + 6y = -34
-x + 3y = -17
x = 3y +17
Sub this into 1st eqn
5(3y + 17) + 2y = 21
15y + 85 + 2y =21
17y = -64
y = -3.7647 (to 5 sig. fig.)
y = -3.8 (to nearest tenth)
Sub y = -3.7647 into 2nd eqn
x = 3(-3.7647) +17
x = 5.7 (to nearest tenth)
16.5 degrees below the starting temp, whatever that is. If its 0, then -16.5 degrees.
The first equation would be (.5)5-11=-8.5, because the metal has been cooling for 5 hours.
The device that 'aids' in the cooling would be -5-3=-8, because it is a separate variable that cools the metal, so the amount the device cools is independent of the natural cooling amount, and the equation is independent of the natural cooling equation.
You then add -8.5 and -8, because the device has lowered 8.5 degrees and 8 degrees. This equals -16.5 degrees, or a decrease of 16.5 degrees.