Answer:
90+30+2x=180
Step-by-step explanation:
2x is an angle, so we need to find its measure
square symbol at corner of triangle means 90 degrees
we know the angle at the top corner is 30 degrees
the sum of all the angles in a triangle is 180 degrees
so the sum of 90 degrees, 30 degrees, and 2x degrees is 180 degrees
translate it to mathematical format: 90+30+2x=180
