The coordinates of the vertices of the triangle are
(–8, 8), (–8, –4), and<span> (10, –4)</span>.
Consider QR the base of the triangle. The measure of the base is b = 18 units, and the measure of the height is h = <span>12</span> units.
The area of triangle PQR is<span>108</span> square units.
Let r = usual driving rate
let t = usual driving time
We need to figure out t
The distance she covers in her usual time at her usual rate is r*t
The distance she covers in her new time at her new rate is:
(1+t)*((2/3)r)
Set this equal to each other and solve for t.
rt = (2/3)r + (2/3)rt
(1/3)rt = (2/3)r
(1/3)t = (2/3)
t = 2
So her usual time is 2 hours. (There's probably a faster way to do this)
