Answer:
8
Step-by-step explanation:
So, lets go over a few things:
First off, all triangles have a total angle of 180 degrees.
Secondly, we know that the first two angles are 57 and 51.
Thirdly, we know that the missing angle is 9x
To solve this, we must add together the known angles, subtract them fro 180, and divide that by 9. This will give us the missing x value.
So, add together the two angles we know:
57+51
=
108
So we know 108 degrees of our triangle. We must find whats left of the 180.
To do this, subtract 108 from 180:
180-108
=
72
So our remaining angle is 72 degrres.
But recall that x isnt the misisng angle, 9x is.
So, to get x on its own, we must divide both the missing angle and 9x by 9:
72=9x
--- ---
9 9
=
8=1x
So now we know that x equals 8.
I hope this helps! :)
