Do I just set it equal to 180? or am i wrong

AB=18 units.

Step-by-step explanation:

So, one of the angle measures is 6x. Since the shape is an equilateral triangle, this means that all the angles measure 6x. In other words, the total measure of the three angles is 6x+6x+6x=3(6x) or 18x. Recall that a triangle has a total interior angle sum of 180. Therefore, set 18x to 180 and solve for x:

Divide both sides by 18:

Therefore, x is equal to 10.

Now, since this is an equilaterial triangle, all three side lengths are the same. Thus, AB=BC=AC. We know that BC is equal to x+8. Find BC:

And since all the side lengths are equivalent, this means that side AB is also 18 units.

See below.

Step-by-step explanation:

The 3 angles in the triangle add up to 180 degrees

Also, as all 3 sides are equal, all 3 angles are also equal and each has the value 180/3 = 60 degrees.

So 6x = 60

x = 10.

Now AB = BC = x + 8

Therefore AB = x + 8

= 10 + 8

= 18.

answer: 12

step-by-step explanation: