Question

What is the slope of a line that is perpendicular to the line whose equation is 2x+7y=5?A. 7/2B. 2/7C. −7/2D. −7/5

Answer 1

We have the followed expression for a giving line:

`2x+7y=5`

Isolating the Y we find the expression:

`y=(-2)/(7)x\text{ + }(5)/(7)`

We know that if a line with expression y=mx+b is perpendicular to the line that the question gave to us, the product of the slopes of the two lines must be:

`(-2)/(7)* m=-1`

With this last expression, we can find the slope for the line perpendicular to our first line:

`(-2)/(7)* m=-1\text{ }\Rightarrow\text{ m=}(7)/(2)`

So, our slope is 7/2