129k views
3 votes
Help with solving for the variable in math problem: -3(3x)^2 + 3 = -6

2 Answers

1 vote

To solve this problem, we first need to do the exponents (PEMDAS).


(3x)² is equal to 9x² Now we can substitute this back.


-3(9x²) + 3 = -6


Now we do multiplication


-27x² + 3 = -6


Now we can subtract 3 from each side to get the x on one side.


-27x² = -9


We can now divide each side by -27.


x² = 1/3


x =
\sqrt{(1)/(3)}


x = -
\sqrt{(1)/(3)}

User Master Bee
by
6.4k points
2 votes

Answer

x = 1/√3 and x = -1/√3

or in decimals x = + 0.577350269 and

= - 0.577350269


Step-by-step explanation

-3(3x)² + 3 = -6

-3×9x² + 3 = -6

-27x² = -6-3

-27x² = -9


x² =-9/(-27)

= 9/27


x = +√(9/27)

x = 3/√27

= 3/√9×3

= 3/3√3

= 1/√3

or in decimals x = 0.577350269

Also x = -√(9/27)

x = +√(9/27)

x = -3/√27

= -3/√9×3

= -3/3√3

= -1/√3

or in decimals x = -0.577350269

User Vineet Kasat
by
7.3k points