Question

Solve the system by substitution 3x+y=-16 and y=-x-4

Answer 1

Solution,

y = -x-4......(i)

3x + y =- 16.......(ii)

Now,

Substituting the value of y in equation (ii)

or, 3x + (-x-4)= -16

or,3x - x - 4 = -16

or, 2x= -16 +4

or, x = -12/2

: x = -6

Then,

Substituting the value of x in (i) equation;

or,y= -(-6) - 4

or,y= 6 - 4

: y =2