Mark incorrectly solved the equation -2(x – 3) – 5 = 9. His steps are shown below: ( its the attached image )
Please Help Me Solve These Two Questions
1. Mark made two mistakes. Identify which line Mark made his first mistake in and explain to Mark what he did wrong.
2. Mark made two mistakes. Identify which line Mark made his second mistake in and explain to Mark what he did wrong.

geometry: triangles

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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

a mantle plume is an upwelling of abnormally hot rock within the earth's mantle. as the heads of mantle plumes can partly melt when they reach shallow depths, they are thought to be the cause of volcanic centers known as hotspots and probably also to have caused flood basalts.

step-by-step explanation: