I suspect 4/2 should actually be 4/3, since 4/2 = 2, while 4/3 would make V the volume of a sphere with radius r. But I'll stick with what's given:
In Mathematica, you can check this result via
D[4/2*Pi*r^3, r]
9514 1404 393
Answer:
r = 1/9
Step-by-step explanation:
First of all, solve the equation for r:
y = rx
y/x = r . . . . . . . divide by x
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Since r is a constant, it will be the same for any corresponding pairs of x and y. It is convenient to choose both x and y as integers, as in the third table entry.
r = y/x = 5/45
r = 1/9 . . . . . . . . . reduced fraction
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<em>Additional comment</em>
It is not a bad idea to check to see that this works with other values of x and y. For the first line of the table, we have x = 11:
y = rx = (1/9)(11) = 11/9 = 1 2/9 . . . . matches the table value
If we were to foil
after experieence
we know
ax²+bx+c=0
and
in form
(ax+b)(cx+d)=0
if we expand it, we get
acx²+bcx+adx+bd=0
or
(ac)x²+(bc+ad)x+(bd)=0
compare to
ax²+bx+c=0
we notice that the middle terms (x terms) are
b=(bc+ad)
so
in form
(2x-1)(1x+5)
b=bc+ad=(-1*1+2*5)=-1+10=9
b=9
or you could just expand it
Answer:
5.4
Step-by-step explanation:
