Answer:
85
Step-by-step explanation:
So you train of though might lead you to soemthing like this: it must be 90 degrees, since that looks like a 90 degree triangle, and there are 180 degrees in a line. So 90 degrees and 90 degrees make up the 180.
That is exactly what I though.
But, its a bit different from that. We do not know for sure that its a 90 degree traingle. Depending on the angle of the traingle, the outcome of the mystery number is different.
So, to find the angle of the trainge, lets take our 155 degree line.
Now, this is just a simple line. We know the line is 180, and that the other number must add onto 155 to make 180:
180-155=missing angle
=
25. So we know that the smallest angle of the traingle is 25.
We also know that a traingle has a total of 180 degrees.
We can add the 60 degrees and our new 25 degrees, subtract if from 180, and we will get our last angle of the traingle we need to solve:
60+25
=
85
Now subtract it from 180:
180-85
=
95
So that last angle of the traingle is 95.
Now, we need to solve the missing angle of the line that will give us the answer.
Again, we know the line has to be 180, so lets subtract 95 from that:
180-95
=
85
So we know that the missing angle answer is 85!
I hope this isnt too confusing and helps! :)
