Two negatives equal a positive, so its just like subtracting 50 and 30, but your answer will be a positive.
40 - x^2 = 0
x^2 = 40
x = + 40^0.5 or x = - 40^0.5
X equals to 48
The work is shown in the picture. I hope this helps.
I'll do the first two to get you started
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Problem 1
A = 3 = starting value
B = 10 = ending value
C = percent change
C = [ (B - A)/A ] * 100%
C = [ (10-3)/3 ] * 100%
C = (7/3) * 100%
C = 2.3333333 * 100%
C = 233.33333%
C = 233.3%
The positive C value means we have a percent increase. If C was negative, then we'd have a percent decrease.
<h3>Answer: 233.3% increase</h3>
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Problem 2
A = 9 = start value
B = 20 = end value
C = percent change
C = [ (B - A)/A ] * 100%
C = [ (20-9)/9 ] * 100%
C = (11/9)*100%
C = 1.2222222222*100%
C = 122.22222222%
C = 122.2%
<h3>Answer: 122.2% increase</h3>
