Answer:
7 cm
Step-by-step explanation:
An equilateral triangle has all sides equal.
To find the measure of the side, simply divide the perimeter by 3. This is because a triangle has 3 sides.
21 ÷ 3 = 7
Answer:
135 degrees
Step-by-step explanation:
all the angles in a triangle need to add to 180 degrees, so you take
180-(65+70)= 45
Then you just find the supplementary angle
45+x=180
x=135
X=-3
7+4x=-5
-7 -7
4x=-12
/4. 4/
X=-3
