Tonya is 1.3 meters tall. she stands 7 meters in front of a tree and casts a shadow of 1.8 meters long. how tall is the tree

The tree is  6.36  meters tall.

Explanation:  Let AB is tree of height  h t = ?  and CD is Tonya  h g = 1.3  meter tall at  A C =  7 meters in front of tree . The shadow  C E = 1.8  meters long .  So two similar triangles are formed , one  Δ A E B and other  Δ C E D . So  A B C D = A E C E  or  h t h g = A E A C  or   h t h g = A C + C E  AC  or  h t  1.3 = 7 + 1.8 1.8  or  h t = 8.8 ⋅ 1.3 1.8 ≈ 6.36 ( 2 d p )m

The tree is  6.36  meter tall.