Answer:
if give brainliest i will answer
Step-by-step explanation:
Answer:
<h2>x= -3</h2>
Step-by-step explanation:



Add 7 to both sides

At the left hand side 7 will cancel 7
At the right hand side 7 will add up

Divide through by 2

simplify the fraction

Name three quaderlateral that only sometimes have right angle
Rhombus, trapezoid, and parallelogram
Since it's an equilateral triangle, all of the angles are the same. Since its perimeter we just need to add. So 3.5+3.5+3.5= 10.5
So the answer is 10.5