Question

no is the solution correct
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Answer 1

no there is a mistake after the step h=50

Answer 2

2 pi r h + pi r^2 = 3000
h=50
100 pi r + pi r^2 = 300

Answer 3

r^2 +100 r -300/pi = 0
can you solve this quadratic ?

Answer 4

no iam confused we have to find r here

Answer 5

yes, thats the quadratic equation in r
can you solve quadratics ?

Answer 6

i dont get it where will position h

Answer 7

h is already given to be 50 and we have used it.
we only need r now.

Answer 8

r^2 +100 r = +95.59

Answer 9

write that as
r^2 +100r -95.59 =0
and use the quadratic formula.

Answer 10

Compare your quadratic equation with \(ax^2+bx+c=0\)
find \[a=...?\\b=...?\\c=...?\\\] \[ \\ \sqrt{b^2-4ac}=...?\]
then the two roots of x are:
\(\huge{x_{1,2}=\frac{-b \pm \sqrt{b^2-4ac}}{2a}}\)

Answer 11

I think your equation should read
\[ \pi r^2 +100 \pi r -3000 = 0 \]
after dividing by pi (to simplify the r^2 term)
\[ r^2 +100 r -\frac{3000}{\pi} = 0 \]
or (using pi= 3.1416), roughly
\[ r^2 +100 r - 954.93 =0 \]

Answer 12

you definitely need a calculator to solve for r