Question

Which equation is the slope-intercept form of the line that passes through (12, 9) and is perpendicular to the graph of y = −3/4x + 1?

Answer 1

first, we know it will be perpendicular to a line with a slope -3/4

and a line to be perpendicular must be inverse and with an inverted sign, so the slope of our line is: 4/3

so the slope form is:

`y=(4)/(3)x+b`

and we can find b replacing x and y for the point (12,9)

`\begin{gathered} 9=(4)/(3)\cdot12+b \\ 9=16+b \\ b=9-16=7 \end{gathered}`

so the answer is: Option A

`y=(4)/(3)x-7`