Find the value of a so that the lines with the given equations are perpendicular: y=2x+13 6y+ax= 6.

Ineed to know the answer to this algebra question.

Ireally need subtract and simplify.(-y^2 – 4y - 8) – (-4y^2 – 6y + 3)show your work, ! i will mark you brainliest but you have to show your work.

Need plz been trying to do it for a long time and still haven’t succeeded