Question

How do I solve: x^2+3=84.

Answer 1

Answer:

x = -9

x = 9

Step-by-step explanation:

$x^{2} + 3 = 84$

Subtract 84 from both sides.

$x^{2} + 3 - 84 = 0$

Subtract 84 from 3 to get −81.

$x^{2} - 81 = 0$

Consider $x^{2}$ - 81. Rewrite $x^{2} - 81$ as $x^{2} - 9^{2}$. The difference of squares can be factored in using the rule: $a^{2} - b^{2} = ( a- b) ( a+ b)$.

$(x - 9) (x + 9) = 0$

To find equation solutions, solve $x - 9 = 0$ and $x + 9 = 0$

x = 9

x = -9

Hope it helps and have a great day! =D

~sunshine~

Answer 2

Answer:

x=9, x=-9

Step-by-step explanation:

subtract 3 from both sides

x^2=81

then squareroot both sides (remember that there is a positive and negative solution!)

x=9, x=-9