RES
Town Q and Town P were 119 km apart. Van drove from
Town Q to Town P at an average speed of 70 km/h. How
much sooner would he have arrived at Town P if he had
travelled at an average speed of 85 km/h instead?
min

2x^2+5x+17

your welcome. : )

geometry: triangles

solvers

lessons

answers archive

call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584