# What is the equation of the line perpendicular to #y=-2x # that passes through # (4,-1) #?

##### 1 Answer

#### Explanation:

Suppose the slope (gradient) of the original equation was m. Then we would have:

The line perpendicular would have the gradient of

So for your equation

That means that the line perpendicular will have the gradient of

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So the new equation is:

The thing is that it should be

where c is a constant value

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We are given that

So by substitution we have: