Question

which equation describes a line that passes through (-5,-8) and is perpendicular to y=5/4x+10A. y=-0.8x+10B. y=-1.25x-14.25C. y×y=-1.25x-1.75D. y=-0.8x+3

Answer 1

Let's begin by listing out the information given to us:

$(x,y)=(-5,-8)$

This is perpendicular to the line

$y=\frac{5}{4}x+10$

The equation is already in the slope-intercept form:

$\begin{gathered} y=\frac{5}{4}x+10 \\ slope(m)=\frac{5}{4} \end{gathered}$

The slope of the parallel line is given by:

$\begin{gathered} m(perpendicular)=-\frac{1}{m} \\ m=\frac{5}{4} \\ m(perpendicular)=-\frac{1}{\frac{5}{4}}=-\frac{4}{5} \\ m(perpendicular)=-\frac{4}{5}=-0.8 \end{gathered}$

We proceed by substituting the values of x & y into the new equation, we have:

$undefined$