Question 1073898
.
Solve by completing the square:

{{{-3x^2+1}}} = {{{4x }}}

Thanks!!!
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<pre>
{{{-3x^2+1}}} = {{{4x }}}  <---->  {{{-3x^2 - 4x}}} = {{{-1}}}  <--->   

{{{-3*(x^2 + (4/3)x)}}} = {{{-1}}}  <---->  {{{x^2 + (4/3)x}}} = {{{1/3}}}  <---->  {{{x^2 + 2*(4/6)x + (4/6)^2}}} = {{{(4/6)^2 + (1/3)}}} <---->  

{{{x^2 + 2*(2/3)x + (2/3)^2}}} = {{{(2/3)^2 + (1/3)}}}  <---->  {{{(x+2/3)^2}}} = {{{4/9 + 1/3}}}  <---->  {{{(x+2/3)^2}}} = {{{4/9 + 3/9}}}  <---->  {{{(x+2/3)^2}}} = {{{7/9}}}  <---->

{{{x + 2/3}}} = +/- {{{sqrt(7/9)}}}  <---->  x = {{{-2/3 +- sqrt(7/9)}}}  ---->

There are two solutions:

{{{x[1]}}} = {{{-2/3 + sqrt(7)/3)}}} = 0.215 (approx.),   and   {{{x[2]}}} = {{{-2/3-sqrt(7)/3}}} = -1.55 (approx.).
</pre>

Solved.


Plot:


{{{graph( 330, 330, -3.5, 3.5, -5.5, 5.5,
          -3x^2 + 1 - 4x 
)}}}


Plot y = {{{-3x^2 + 1 - 4x}}}