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12 songs. 25% of 12 is 3, so you add 3 to 12 and get 15. You then find that 20% of 15 is 3 so you subtract 3 from 15 and get 12 again.
N² - 49 = 0
<u> + 49 + 49</u>
n² = 49
n = <u>+</u>7
The solution to the problem is {7, -7}.
0.08x+(x-200)
(0.08x)(x+-200)
(0.08x)(x)(0.08x)(-200)
= 0.08x^2-16x
They are all even numbers