Question

Equations that represent a line which is perpendicular to the line y=-1/8x+3

Answer 1

The equation of a line in slope intercept form is given as

`\begin{gathered} y=mx+b \\ where\text{ m is slope and b is intercept on the y-axis } \end{gathered}`

Comparing this to

`\begin{gathered} y=-(1)/(8)x+3 \\ the\text{ the slope m = -}(1)/(8) \\ and\text{ the intercept b = 3} \end{gathered}`

For two lines to be perpendicular, their product of their slope should be = -1

So we have

`\begin{gathered} m_1m_2=-1 \\ -(1)/(8)* m_2=-1 \\ m_2=(-1)/(-(1)/(8)) \\ =-1*-(8)/(1) \\ =(8)/(1) \\ =8 \end{gathered}`

So the equation of the line becomes

`y=8x+3`

So the best choice should be one with slope of 8

If you bring 8x to meet y, we have

`y-8x=3`

So the correct answer is the equation looking like this above

So the best answer is

y - 8x = -2, the last option is the answer