Question 109479



{{{3x+5y=56}}}

{{{y= 66-8y / 5}}}…..I guess, here should be {{{8x}}}, not {{{8y}}}

{{{3x+5y=56}}}

{{{y= 66-8x / 5}}}…..you can solve this for {{{y}}} and substitute this {{{y}}} value in first equation and find out what is {{{x}}} equal to


{{{3x + 5 ((66-8x) / 5) = 56}}}……here we can cancel {{{5}}}

{{{3x +  66 - 8x  = 56}}}……

{{{- 5x + 66  = 56}}}……move {{{-5x}}} to the right, and {{{56}}} to the left


{{{ 66 - 56 = 5x}}}……

{{{ 10  = 5x}}}……divide both sides by {{{5}}}

{{{x = 2}}}

Now find {{{y}}}

{{{3x+5y=56}}}

{{{3*2+5y=56}}}

{{{5y=56 - 6}}}

{{{5y=50}}}…….. divide both sides by {{{5}}}

{{{y = 10}}}



2. in case you did write your second equation correctly, you will do it this way

{{{3x + 5y = 56}}}

{{{y = 66 - 8y / 5}}}…..solve for {{{y}}}

{{{y= 66 - 8y / 5}}}…..multiply both sides by {{{5}}}

{{{5y = 66*5 – (8y)/5*5}}}
{{{5y = 330 – 8y}}}…move {{{-8y}}} to the left

{{{5y + 8y = 330}}}

{{{13y = 330}}}

{{{y = 330/13}}}

{{{y = 25.38}}}……..substitute this in first equation and find {{{x}}}


{{{3x + 5y = 56}}}……..move {{{5y}}} to the right

{{{3x = -5y + 56}}}

{{{3x = -5(25.38) + 56}}}

{{{3x = -126.9+ 56}}}

{{{3x = -70.9}}}

{{{x = -70.9/3}}}

{{{x = -23.63}}}