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How do you solve #49a^2-1=80#?

Answer 1

Nathan Axel

#a=+-9/7#

#49a^2-1=80#

#49a^2-81=0 rarr# This is an example of difference of squares

Difference of squares: #a^2-b^2=(a+b)(a-b)#

#(7a+9)(7a-9)=0#

#7a+9=0#

#7a=-9#

#a=-9/7#

#7a-9=0#

#7a=9#

#a=9/7#

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Answer 2

Isaiah Anthony

To solve the equation (49a^2 - 1 = 80), first, add 1 to both sides to isolate the term with (a^2). Then, divide both sides by 49 to solve for (a^2). Finally, take the square root of both sides to find the values of (a). The solutions are (a = \pm \sqrt{\frac{81}{49}}), which simplifies to (a = \pm \frac{9}{7}).

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.