Solving systems with substitution (K-A)

• Systems of equations with substitution: 2y=x+7 & x=y-4 (K-A)
• Systems of equations with substitution (K-A)
• Systems of equations with substitution: y=4x-17.5 & y+2x=6.5 (K-A)
• Systems of equations with substitution: 9x+3y=15 & y-x=5 (K-A)
• Systems of equations with substitution: y=-5x+8 & 10x+2y=-2 (K-A)
• Systems of equations with substitution: y=-1/4x+100 & y=-1/4x+120 (K-A)