Question

Which equation represents a line which is Parallel to the line x+3y=-21

Answer 1

a line with a gradient of

`( - x)/(3)`

Explanation:

parallel lines have equal gradients, i.e the value of m, has to be the same.

therefore:

`x + 3y = - 21 \\ 3y = - x - 21 \\ y = ( - x)/(3) - 7`