Question

Find obtuse angle between the pair of line.
3x-y+6=0 & y+2x=5​

Answer 1

3x-y+6=0.......(1)

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

[m1]slope of line 1=- coefficient of x/coefficient of y=3

[m2]=slope of line 2=- coefficient of x/coefficient of y=-2

we have

tan ø=
`(m1 - m2)/(1 + m1m2)`

tan ø=
`(3+2)/(1 + 3×-2)`

tan ø=
`(5)/(-5)`

tan ø=-1

ø=135°

obtuse angle between the pair of line is 135°