Question

Find an equation perpendicular to X equals one and passing through the points -7, -4

Answer 1

We need to find an equation perpendicular to x=1 that passes through (-7,-4). x=1 is a straight line so the graph of a perpendicular equation must also be a straight line. This means that the equation we are looking for has the form:

`y=mx+b`

Since x=1 is a vertical line on the grid this means that any horizontal line is perpendicular to it. Then, the slope of the perpendicular equation must be 0 i.e. m=0. So for now we have:

`\begin{gathered} y=0\cdot x+b \\ y=b \end{gathered}`

In order to find b and complete the equation we must use the fact that this line passes through (-7,-4). The y coordinate of this point is -4 which means that y=-4 and since y=b we have that b=-4 and the equation we are looking for is:

`y=-4`