No, Yin is not correct. If x = 19, the measure of angle ABC = 4(19) – 12 = 64. Therefore, the two base angles measure 64°. An equilateral triangle is equiangular, so each angle would have to measure 60° because there are 180° in a triangle.
Yin is incorrect because when the value of x is 19 both the angles is equal to [tex]64^\circ[/tex] but in equilateral triangle all the angles must be equal to [tex]60^\circ[/tex] and this can be determine by using the properties of equilateral triangle.
Given :
In triangle ABC, [tex]\angle[/tex]ABC = (4x – 12)° and [tex]\angle[/tex]ACB = (2x + 26)°.
In equilateral triangle all the three sides of the triangle are equal and all the interior angles are congruent to each other and equal to [tex]60^\circ[/tex].
So, to prove that the given triangle ABC is an equilateral triangle than both the given angles must be equal to [tex]60^\circ[/tex].
[tex]=4\times19-12[/tex]
= 76 - 12
= [tex]64^\circ[/tex]
[tex]= 2\times 19 + 26[/tex]
= 38 + 26
= [tex]64^\circ[/tex]
Therefore, Yin is incorrect because when the value of x is 19 both the angles is equal to [tex]64^\circ[/tex] but in equilateral triangle all the angles must be equal to [tex]60^\circ[/tex].
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https://brainly.com/question/6238271
