Do you remember the special case of factoring the difference of 2 squares ?
x² - 5 = (x + √5) (x - √5)
That will be zero if either factor is zero.
First factor:
x + √5 = 0
<u>x = -√5</u>
Second factor:
x - √5 = 0
<u>x = √5</u>
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Another way to look at it is just to sit there and LOOK at it.
<u>x² - 5 = 0</u>
x² = 5
This is true if x = + or - √5 .
4/31. There's no more simplified version than that.
So
if increase by 10%, that means times 1.1
sub 1.1r for r in
V=(4/3)pir³
so
nV=(4/3)pir³
nV=(4/3)pi(1.1r)³
nV=(4/3)pi1.331r³
nv=((4/3)pir³)1.331
V=(4/3)pir³
nV=(V)1.331
x times 1.331 is about a 33% increase
Answer: B
Step-by-step explanation: r≈21.01ft