Question

Are the lines `x+2y=7` and `2x+4y=21` parallel, perpendicular, or neither?

Answer 1

Both the lines have equal slopes hence they are parallel

Explanation:

`x+2y=7`
or
`2y=7-x`
or
`y=-x/2+7/2`
`y=mx+c` where mis the slope
So from above equation we get slope `=-1/2`
Similarly
`2x+4y=21`
or
`4y=-2x+21`
or
`y=-2x/4+21/2`
or
`y=-x/2+21/2`
So similarly from above equation we get slope `=-1/2`
Both the lines have equal slopes hence they are parallel