Help plz ASAP and explain the answer
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Given:
It is given that the measurements of the triangle.
The measure of ∠2 is (3x + 3)°
The measure of ∠3 is (3x - 4)°
The measure of ∠4 is (5x + 8)°
We need to determine the measure of ∠1 and ∠4.
Value of x:
The value of x can be determined using the exterior angle theorem.
Applying the theorem, we have;
[tex]m \angle 4=m \angle 2+m \angle 3[/tex]
Substituting the values, we get;
[tex]5x+8=3x+3+3x-4[/tex]
[tex]5x+8=6x-1[/tex]
[tex]-x+8=-1[/tex]
[tex]-x=-9[/tex]
[tex]x=9[/tex]
Thus, the value of x is 9.
Measure of ∠4:
Substituting the value of x in the expression of ∠4, we get;
[tex]m\angle 4=5(9)+8[/tex]
[tex]=45+8[/tex]
[tex]m\angle 4=53^{\circ}[/tex]
Thus, the measure of ∠4 is 53°
Measure of ∠1:
The angles 1 and 4 are linear pairs and hence these angles add up to 180°
Thus, we have;
[tex]\angle 1+ \angle 4=180^{\circ}[/tex]
Substituting the values, we get;
[tex]\angle 1+ 53^{\circ}=180^{\circ}[/tex]
[tex]\angle 1=127^{\circ}[/tex]
Thus, the measure of ∠1 is 127°