SOLUTION
Given the question in the image, the following are the solution steps to answer the question.
STEP 1: Define Similar triangles
Similar triangles are triangles that have the same shape, but their sizes may vary. All equilateral triangles, squares of any side lengths are examples of similar objects. In other words, if two triangles are similar, then their corresponding angles are congruent and corresponding sides are in equal proportion.
STEP 2: Write the ratio of the corresponding sides

STEP 3: Add 6 units to each side length of both triangles and write the new corresponding ratios

It can be seen that with addition of 6 units, the triangles stop to follow the similarity rules because the ratios of the new corresponding sides are not the same.
Hence, the answer is "No, the two new triangles will not be similar"