4 is the square root of 16
i think that what you are asking, but if it is not tell me and i can try to help more :)
A² - 225 = (a-15)(a+15)
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Step-by-step explanation:
(x+1)squared-squared=2x+1 is always odd because sum of even number and odd number is always odd
Try to calculate them in your head and if that doesn't help use a calculator. I hope this helps
Step-by-step explanation:
in a geometric sequence there is a constant factor x that is multiplied with every previous term to create the next one.
a2 = 20
a5 = 1280 = a2×x×x×x = a2×x³ = 20x³
64 = x³
x = 4
=> a1 = 5
therefore
an = an-1×4 =

n > 1