Question

Please help me with numbers four and five in the picture please the instruction say to solve the systems of simultaneous equations by using the substitution method check your work

Answer 1

#4

• y=-x=>x+y=0--(1)
• 3x+y=4--(2)

Subtracting both

• -2x=-4
• x=2

Putvin first one

• 2+y=0
• y=-2

#5

y=x-1

• x-y-1=0--(1)
• 4x-y-19=0--(2)

Subtract both

• -3x+18=0
• x=6

Put in first one

• 6-y-1=0
• 5-y=0
• y=5