Problem: Solve 10x+5y=72;15x+4y=80 Steps: I will try to solve your system of equations. 10x+5y=72;15x+4y=80 Step: Solve10x+5y=72for x: 10x+5y+−5y=72+−5y(Add -5y to both sides) 10x=−5y+72 10x 10 = −5y+72 10 (Divide both sides by 10) x= −1/2 y+36 5 Step: Substitute −1 2 y+ 36 5 forxin15x+4y=80: 15x+4y=80 15( −1 2 y+ 36 5 )+4y=80 −7 2 y+108=80(Simplify both sides of the equation) −7 2 y+108+−108=80+−108(Add -108 to both sides) −7 2 y=−28 −7 2 y −7 2 = −28 −7 2 (Divide both sides by (-7)/2) y=8 Step: Substitute8foryinx= −1 2 y+ 36 5 : x= −1 2 y+ 36 5 x= −1 2 (8)+ 36 5 x= 16 5 (Simplify both sides of the equation) Answer: x=16/5 and y=8