find The value of x, y and z
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Answer:
x = 18 ; y = 10 ; z = 102°
Step-by-step explanation:
The triangle in the pic is an isosceles triangle.
As it is an isosceles triangle , it's two sides will be equal .
[tex] = > 3x - 42 = 12[/tex]
[tex] = > 3x = 42 + 12 = 54[/tex]
[tex] = > x = \frac{54}{3} = 18[/tex]
Also, both the base angles will be equal.
[tex]4y - 1 = 39[/tex]
[tex] = > 4y = 39 + 1 = 40[/tex]
[tex] = > y = \frac{40}{4} = 10[/tex]
According to angle sum property of a triangle , sum of measure of all the angles of a triangle is equal to 180°. So,
[tex]z + 39 + 39 = 180[/tex]
[tex] = > z + 78 = 180[/tex]
[tex] = > z = 180 - 78 = 102[/tex]