Question

Write an equation for a line parallel to y = − 2 x + 4 and passing through the point ( 2 , 1 )

Answer 1

x=2y

Explanation:

y=-2x+4 is perpendicular to the line which passes through (2,1). We know that we can use the formula y=mx+c to find the gradient of the line with the equation y=-2x+4, which will give you -2. The product of the gradient of two perpendicular lines is always -1. So the gradient of the line which passes through (2,1 ) is -½.

Now,to find the equation of the line,we use the formula y-y1=m(x–x1)which will give you the answer 2y=x when solved.