I'm pretty sure i'm doing this wrong. a little ? in advance.

I believe by "redraw" you are expected to separate the given triangle into the 3 similar-triangle components. You've almost done this correctly - the leftmost triangle should have its hypotenuse labeled .

Then use the similarity between them to establish an appropriate equation. For example, the first triangle contains the three triangles RST, SPT, and RPS. Because these triangles are similar, we have the relationship

In the second triangle, we have

Question 3 uses the same setup as question 1, so you should get .

(n^3 - n)

= n(n-1)(n+1)

since it is divisible by 3 and 2 ,because it is a multiple 3 consecutive number

if, n-1 is odd then n+1 is also odd, then it is a multiple of 9

but if, n-1 is even then n+1 is also even, then it is a multiple of 4

so, largest multiple = max(9*2, 4*3) = max(18, 12) = 18