Question

3x – 4y – 15 = 0 and y + x + 2 = 0. 

can these equations be solved by eliminating x ? Is the solution same?

Answer 1

3x – 4y – 15 = 0 

∴ 3x – 4y = 15 …(i) 

y + x + 2 = 0 

∴ x + y = -2 ……(ii)

Multiplying equation (ii) by 3,

 3x + 3y = -6 …(iii) 

Subtracting equation (iii) from (i),

∴ y = -3 

Substituting y = -3 in equation (ii), 

∴ x – 3 = -2 

∴ x = – 2 + 3 

∴ x = 1 

∴ (x, y) = ( 1, -3) 

Yes, the given equations can be solved by eliminating x.

Also, the solution will remain the same.