find the value of z

Check the picture below.
[tex]2x+15~~ = ~~\cfrac{(10x+20)-80}{2}\implies 4x+30=10x-60 \\\\\\ 4x+90=10x\implies 90=6x\implies \cfrac{90}{6}=x\implies \boxed{15=x} \\\\[-0.35em] ~\dotfill\\\\ \stackrel{\textit{the whole circle is}}{z + 80 + (10x+20)}~~ = ~~\stackrel{degrees}{360}\implies z+80+[10(15)+20]~~ = ~~360 \\\\\\ z+250=360\implies \blacktriangleright~~ z=110 ~~\blacktriangleleft[/tex]
If the value of x is 15 degrees. Then the measure of the arc z will be 110 degrees.
It is the centre of an equidistant point drawn from the centre. The radius of a circle is the distance between the centre and the circumference.
The diagram is shown below.
[tex]\rm 2x + 15 = \dfrac{10x + 20 - 80 }{2}[/tex]
Then the value of x will be
4x + 30 = 10x - 60
6x = 90
x = 15
Then the value of (10x + 20) will be
(10x + 20) = 10 × 15 + 20
(10x + 20) = 150 + 20
(10x + 20) = 170
Then the measure of the arc z will be
z + 170 + 80 = 360
z = 110
More about the circle link is given below.
https://brainly.com/question/11833983
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