Question

I need answers for this.

Answer 1

We understand as the perimeter of a triangle as being the sum of all of its sides. So if we sum up all the sides of the triangle we should get this:

$3b +5 + 12 + 6b + 1 = 9b + 18$

So the equation for the perimeter of the triangle is 9b + 18.

Since the value of the perimeter of the triangle is given, we can simply conclude that:

9b + 18 = 45

Answer 2

D.

1)
Perimeter of the triangle
P = 12 + 6b + 1 + 3b + 5
P = 9b + 18


2) perimeter = 45 cm

Equation:
9b + 18 = 45