I will try to solve your system of equations.
x+y=120;5.25x+3y=517.2
Step: Solvex+y=120for x:
x+y+−y=120+−y(Add -y to both sides)x=−y+120
Step: Substitute−y+120forxin5.25x+3y=517.2:
5.25x+3y=517.25.25(−y+120)+3y=517.2−2.25y+630=517.2(Simplify both sides of the equation)−2.25y+630+−630=517.2+−630(Add -630 to both sides)−2.25y=−112.8−2.25y−2.25=−112.8−2.25(Divide both sides by -2.25)y=50.133333
Step: Substitute50.133333foryinx=−y+120:
x=−y+120x=−50.133333+120x=69.866667(Simplify both sides of the equation)
Answer:
x=69.866667 and y=50.133333