Question

Find the equation of the line which is perpendicular 10y +5x =3 and passes through (-7,-1)

P.s. working.

Answer 1

y = 2x +13

Explanation:

when 2 lines are perpendicular, the product of the two gradients is -1

i.e. m x m1 = -1

so from 10y + 5x = 3, the gradient m is -0.5

m1 = -1 / -0.5 = 2

using m1 = 2 and pt(-7,-1),

the eqn is y = (m1)x +c

-1 = 2(-7) + c

c= 13

thus y = 2x +13