Answer:
The second: 
Step-by-step explanation:
![f (x) =4x^2+6x-3\\\\f (x) =4(x^2+\frac64x]-3\\\\f (x) =4[x^2+2\cdot x\cdot\frac34+(\frac34)^2-(\frac34)^2]-3\\\\f (x) =4[(x+\frac34)^2-(\frac34)^2]-3\\\\f (x) =4(x+\frac34)^2-4(\frac34)^2-3\\\\f (x) =4(x+\frac34)^2-\frac94-\frac{12}4\\\\\underline{f (x) =4(x+\frac34)^2-\frac{21}4}](https://tex.z-dn.net/?f=f%20%28x%29%20%3D4x%5E2%2B6x-3%5C%5C%5C%5Cf%20%28x%29%20%3D4%28x%5E2%2B%5Cfrac64x%5D-3%5C%5C%5C%5Cf%20%28x%29%20%3D4%5Bx%5E2%2B2%5Ccdot%20x%5Ccdot%5Cfrac34%2B%28%5Cfrac34%29%5E2-%28%5Cfrac34%29%5E2%5D-3%5C%5C%5C%5Cf%20%28x%29%20%3D4%5B%28x%2B%5Cfrac34%29%5E2-%28%5Cfrac34%29%5E2%5D-3%5C%5C%5C%5Cf%20%28x%29%20%3D4%28x%2B%5Cfrac34%29%5E2-4%28%5Cfrac34%29%5E2-3%5C%5C%5C%5Cf%20%28x%29%20%3D4%28x%2B%5Cfrac34%29%5E2-%5Cfrac94-%5Cfrac%7B12%7D4%5C%5C%5C%5C%5Cunderline%7Bf%20%28x%29%20%3D4%28x%2B%5Cfrac34%29%5E2-%5Cfrac%7B21%7D4%7D)
It equal 1/2 of 2/3 thirds its the same answer before the equal
When multiplying out you get:
x2+4x-3x-12....
so you'd be adding the +4x to the -3x
x2 + x - 12
we know that having similar triangles so the ratio of sides,area and volume are same.

we know that
will be the area of triangle.

so 
so the ratio of the perimeter of two triangles will be

ratio of the perimeter=
I hoped this helped or something