Answer:
Step-by-step explanation:
The first step in solving the equation is to cube both sides:
(∛x)³ = (-4)³ . . . . . = (-4)(-4)(-4) = 16(-4) = -64
x = -64 . . . . . simplified
__
We're not sure what "checking" is supposed to involve here. Usually, one would check the answer by seeing if a true statement is made when the answer is put into the original equation.
∛(-64) = -4 . . . true
Many calculators will not compute √(-64) because they compute roots using logarithms. The log of a negative number is not defined.
So, the way one would check this is to cube both sides, which is how we got the answer in the first place. We expect the same result from doing the same operation again, so it isn't really a check.
We know that
speed=distance/time
solve for time
time=distance/speed
in this problem
<span>Marco runs at a rate of 6 miles per hour.
</span><span>Fernando funs at a rate of 7.2 miles per hour
Difference=7.2-6=1.2 miles/hour
so
speed=1.2 miles/hour
distance=0.3 miles
time=?
</span>time=distance/speed-----> 0.3/1.2-----> 0.25 hour-----> 0.25*60=15 minutes
<span>
the answer is
0.25 hour (15 minutes)
Alternative Method
Let
x---------> Fernando's distance when Marco is 0.3 miles apart
</span>Fernando funs at a rate of 7.2 miles per hour
<span>for distance =x
time=x/7.2------> equation 1
</span>Marco runs at a rate of 6 miles per hour.
for distance=x-0.30
time=(x-0.30)/6------> equation 2
equate equation 1 and equation 2
7.2*(x-0.3)=6x-----> 7.2x-2.16=6x
7.2x-6x=2.16------> x=2.16/1.2-------> x=1.8 miles
time=x/7.2-----1.8/7.2=0.25 hour
<span>Equation:
silver + silver = silver
0.45x + 0.60(40-x) = 0.48*40
----------------
45x + 60*40 - 60x = 48*40
--------
-15x = -12*40
x = (4/5)40
x = 32 lbs (amt of 45% slloy needed)
40-x = 8 lbs (amt of 60% alloy needed)</span>
Answer: The last one is the one with the Median
Step-by-step explanation: Hope this helps ^^