Question 320837
3x - 2.5y = 7.125 multiply by 2.5
2.5x - 3y = 7.3125 multiply by-3 & add.
7.5x-6.25y=17.8125
-7.5x+9y=-21.9375
----------------------
2.75y=-4.125
y=-4.125/2.75
y=-1.5 ans.
3x-2.5*-1.5=7.125
3x+3.75=7.125
3x=7.125-3.75
3x=3.375
x=3.375/3
x=1.125 ans.
proof:
2.5*1.125-3*-1.5=7.3125
2.8125+4.5=7.3125
7.3125=7.3125