What is the solution of the system of equations 2x-5y equals 11and -2x plus 3y equals -9?

Answer 1

2X - 5Y = 11

- 2X + 3Y = - 9

----------------------just add

2Y = 2

Y = 1

--------------now, insert into one of the equations to find X

2X - 5(1) = 11

2X - 5 = 11

2X = 16

X = 8

----------------check in both equations

2(8) - 5(1) = 11

16 - 5 = 11

11 = 11

----------------one checked

- 2(8) + 3(1) = - 9

- 16 + 3 = - 9

- 13 does not equal - 9

---------------------------------an inconsistent system; check with substitution on bottom equation

- 2X + 3Y = - 9

- 2X = - 3Y - 9

X = 3/2Y + 9/2

---------------------insert back into both equations, bottom first

- 2(3/2Y + 9/2) = - 9

-3Y - 9 = - 9

obviously this is inconstant and leads to Y = 0

-----------------------------------------------------------------no need to try top, this system is inconsistent.