Respuesta :

ag6567
SInce the measurements are 7-7-9, the angles must be 80-x-x. So, the value of x is :

2x + 80 = 180
2x = 100
x = 50

Hope this helps!
mwms2018sg
x =50 because the two angles that are not labled are equal because they are symmetrical so a triangle is 180 so 180-80= 100 and 100 divide by 2 is
50