Answer:
40/21
Step-by-step explanation:
-4/7+(-4/3)
common factor is 21
=21/7×-4-21/3×4
=3×-4-7×4 all divided by 21
=-12-28 all divided by 21
=40/21
The sphere. All the others are prisms.
One way to go about this is to first list everything we know in the form of variables. This will make it easier to see how these numbers correlate instead of trying to remember formulas to plug these numbers into.
TimeA = 2.4h (time of Car A to travel)
TimeB = 4h (time of Car B to travel)
SpeedA = SpeedB + 22mph (Speed of Car A<span>)
</span>SpeedB = SpeedA - 22mph (Speed of Car B<span>)
</span>Distance = x (the distance traveled by each car)
We are looking for SpeedA. How can we find this? Well, we know that speed multiplied by time is equal to distance, so let's start there.
SpeedA * 2.4h = x
<span>(SpeedB + 22mph) * 2.4h = x
</span>(2.4h * SpeedB) + 52.8miles = x
We also know that:
SpeedB * 4h = x
Since both of these equations are equal to x, we can combine them:
SpeedB * 4h = x = <span>(2.4h * SpeedB) + 52.8miles
</span>SpeedB * 4h = <span>(2.4h * SpeedB) + 52.8miles
</span>1.6h * Speed B = 52.8miles
SpeedB = 52.8/1.6 mph = 33 mph
<span>SpeedA = SpeedB + 22mph = 33mph + 22mph = 55mph
</span>
Therefore, Car A was traveling at 55mph.
