Question

Solve the system: 2.5(x−3y)−3=−3x+0.5; 3(x+6y)+4=9y+19

Answer 1

Answer:

2.5(x−3y)−3=−3x+0.5

2.5x-7.5y-3=3x+0.5

2.5x-3x-7.5y=0.5+3

0.5x-7.5y=3.5

x- 15y=7. ------------------(1)

3(x+6y)+4=9y+19

3x+18y+4=9y+19

3x+18y-9y=19-4

3x+9y=15

x+3y=5. -----------------(2)

subtraction of equation (1)and(2)

x- 15y=7

x+3y=5

-18y=12

y=-12/18

y=-2/3

y=-2/3put in equation (2)

x+3y=5

x+3(-2/3)=5

x-2=5

x=7

(x,y)=7,-2/3