Question 1152679
given that

{{{y = 2x + 7 }}}
{{{ y = 2x - 4}}} are parallel lines

the line contained by the midsegment is also {{{parallel}}} to lines above and positioned in the {{{middle}}} between them, only difference in equation  is in y-intercept ({{{0}}},{{{y}}})

so, the equation will be {{{ y = 2x +b}}}

find {{{b}}}

it will be half distance between ({{{0}}},{{{-4}}}) and ({{{0}}},{{{7}}}) which is {{{(4+7)/2=5.5}}} units

so, {{{5.5}}} units up from ({{{0}}},{{{-4}}}) ; ({{{0}}},{{{-4+5.5}}}) =({{{0}}},{{{1.5}}})

or, {{{5.5}}} units down from ({{{0}}},{{{7}}}) ; ({{{0}}},{{{7-5.5}}}) =({{{0}}},{{{1.5}}}) 

{{{y = 2x + 1.5 }}}=> your equation


{{{ graph( 600, 600, -10, 10, -10, 10,2x -4 ,2x +7, 2x + 1.5) }}}