What is the value of x?
98°

x = 139

Step-by-step explanation:

Isosceles triangle.

Let the equal angles = y

y + y + 98 = 180   {Sum of all the angles of triangles}

  2y + 98 = 180

          2y = 180 - 98

          2y = 82

           y = 82/2

          y = 41

x = 41 + 98     { exterior angles equals the sum of interior opposite angles}

x = 139

b

step-by-step explanation:

a difference is the result of subtraction. while each of these expressions has subtraction in it, a difference will be the result when subtraction is the last operation applied in the order of operations for the expression. this means subtraction must be outside of the parenthesis. only b has this.