Question

Y=-4-x; domain = {-6, 2,7}

Answer 1

We have to put values of domain to find range

$\\ \ast\sf\longmapsto y=-4-x$

$\\ \ast\sf\longmapsto D_R=[-6,2,7]$

$\\ \ast\sf\longmapsto y=-4-(-6)=-4+6=2$

$\\ \ast\sf\longmapsto y=-4-2=-6$

$\\ \ast\sf\longmapsto y=-4-7=-11$

Now

$\\ \ast\sf\longmapsto R_R=[2,-6,-11]$