If #x^2 +17 = 81#, what is the value of #x#?
2 Answers
The highest power is 2.
Explanation:
Because x has a maximum power of 2, there will be 2 answers. if it were 3, there could be up to 3 answers, etc.
While solving this problem, you gather all terms on one side so the equation looks like
then factor
then, because any number times 0 equals 0, we know that one of the two parts in the parenthesis must be equal to 0, so
and so the two answers
We start by putting all terms to one side of the equal sign:
#x^2 - 81 + 17 = 0#
#x^2 - 64= 0#
Note that
#(x + 8)(x - 8) = 0#
We can now see that if
We can also confirm graphically. If we trace the parabola
Therefore, our answer is correct.
Hopefully this helps!