Christa is standing on the top of head of gladwyn's shadow. If christa is 5 ft tall and Gladwyn's height is 6 feet and the length of their shadows combined is 15 ft, find the length of Christa's shadow

Answer 1

I see 2 similar triangles.
let length of Christa's shadow be x ft
let length of Glad's shadow be y ft

so 5/x = 6/y
6x = 5y

we also know x+y = 15
or y = 15-x

sub into the first:
6x = 5(15-x)
6x = 75-5x
11x = 75
x = 75/11 ft = appr 6.82 ft
y = 15-75/11 = 90/11 ft = appr 8.18 ft