Answer:
104
Step-by-step explanation:
Just separate the whole thing into two shapes. Multiply the first shape: 12 x 7 = 84
Multiply the second shape: 5 x 4 = 20
6 (100) = 600
6 (10) = 60
14 (1) = 14
600+60+14
660+14= 674
- - - - - - - - - - - - - - - - - - - - - - - - - - -

How do you solve this? [question in attachment]

In order to find the perimeter of a shape, we should add all of its sides.
Since a triangle has only 3 sides, we add 3 sides together, like so:-
⇒ 9x-7+12x-13+3x+8
Combine like terms:-
➪ 9x+12x+3x-7-13-8
Which simplifies to
➪9x+15x-7-21
On further simplification,
➪24x-28
So we conclude that the perimeter of the triangle is 24x-28 units.
<h3 /><h3>Good luck.</h3>
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Answer:
the top one
because identity of addition is adding 0