Question

Solve the system by substitution.
{2x-y+z=-4
{ z=5
{-2x+3y-z=-10

Answer 1

put the value of z in the two equations containing z...and bring the two eqn in x an y form

Answer 2

Put the value of z =5 in equation 1
you can use the resulting equation to get y in terms of x
Put this value of y in equation 3.........you will get an equation in single variable which you will be able to solve