Answer:It is The first one.
Step-by-step explanation:
All the angles should add up to 360°.
8x+10x+9+21x-12+90=360°
Group like terms together.
So,8x+10x+21x+9+90-12=360
39x+87=360
39x=360-87
39x=273
x=7
Firstly, It says that the two triangles are similar .
The scale factor is 2 as 12 / 6 = 2
25 + 85 = 110
180 - 110 = 70.
70 degrees
√x ≤ 5
x ≤ 5²
x ≤ 25
hope to helped
