Answer:
Perimeter of both triangles is equal to 21
Step-by-step explanation:
By remembering our triangle facts, we know that the perimeter of a triangle is equal to its lengths added together.
By adding the lengths of triangle ABC we get...
2x + 5 + 2x + 4 + 2x
When we rearrange and add these together we get...
6x + 9
By adding the lengths of triangle PQR we get...
2x + 2x + 3x + 7
When we rearrange and add these together we get...
7x + 7
Because both triangles perimeters are equal we can say that...
6x + 9 = 7x + 7
Now lets solve.
-7 from both sides so we are left with
6x + 2 = 7x
From here we should be able to recognise that by adding our 2 we are just adding 1 lot of x.
Therefore, x = 2.
Use x = 2 solve the perimeter for each triangle to confirm.
