Explanation:
First set the equations equal to each other
4(x-5) = 3x+25
Next multiply the 4 to the x and the 4 to the -5, and you end up getting to
4x-20 = 3x+25
Next combine like terms, subtract the 3x over to the 4x. You end up with 1x aka x.
x-20=25
Now combine more like terms, add the 20 to 25, and you end up getting your x value
x=45
Now substitute the X value into both equations.
4(45-5)
180-20
Angle C = 160 Degrees
3(45) + 25
135+25
Angle Y = 160 Degrees
They are congruent angles, therefore have an equal value of 160 degrees each.
Hope this helped :)