was able to answer part A but can't seem to find the correct terms for the explanation (part b) 'a) work out size of angle x' (which is 80) 'b) give reasons for your answer'

80° is the correct answer

Step-by-step explanation:

The angle B is 100° because of the property of  the vertically opposite angle.

As we know the property consecutive interior angle that the sum of two angle is 180°

So

Angle B + Angle X  =180°

100 °+ Angle X =180°

Angle X=180°-100°

Angle X = 80°

[2, 2.5)

(2.5, 3]

step-by-step explanation:

i think its these two not sure [2, 2.5)

(2.5, 3]

it would be 3 ÷by 6 because the number on each side