Twice the difference of a number and 7 is 9

Astick 2 m long is placed vertically at point b. the top of the stick is in line with the top of a tree as seen from point a, which is 3 m from the stick and 30 m from the tree. how tall is the tree?

Ahiker stands at an unknown elevation before he ascends 2 miles up a mountain to an elevation of 9 miles. find the elevation of the hiker before his ascent.

Deepak plotted these points on the number line. point a: –0.3 point b: – 3 4 point c: – 11 4 point d: –0.7 which point did he plot incorrectly?