x+y=0 এবং 2x-y+3=0 সরলরেখা দুটি কোন বিন্দুতে ছেদ করে?

A (-1/3; 1/3)

B (1;-1)

C (1/3; 1/3)

D (-1;1)

Correct Answer: Option D

the two lines must meet at the point where the x and y co-ordinates are same for both the equations

inorder to solve the equations simultaneously, the substitution method must be applied

therefore from the first equation, we get

x+y=0

x = -y

substituting this equation in thesecond given equation we get

2(-y)-y+3=0

-2y-y+3=0

-3y+3=0

-3y=-3

y=1

substituting y = 1 in any of the two given equations gives us the corresponding value of x

x + (1) = 0

x = -1

therefore the point of intersection of the two straight lines is at the cordinates (-1, 1)