What is the measure of angle 1?
20°
42°
138°
160°
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Step-by-step explanation:
line s || line t
r is the transversal,
Therefore,
(7x-2)°= (6x+18)° {exterior alternate angles}
7x-6x=18+2
x=20°
r is also a straight line,
therefore,
7x-2+angle1=180° (straight angle)
7x-2+ angle1=180°
7(20)-2+ angle 1= 180°
140°-2+ angle 1= 180°
angle 1= (180-140+2 )°= 42°
angle 1= 42°