In the diagram above

140

Step-by-step explanation:

First you have to solve for x

20x + 60 = 30x + 20

so you would subtract 20x from both sides

60 = 10x + 20

then subtract 20 from both sides

40 = 10x

then divide both sides by 10

4 = x

then you would put 4 in for x in the equation for angle 1

20(4) + 60

80 + 60

140

angle 1=20(4)+60=140 degrees

Step-by-step explanation:

theory : If two parallel lines are cut by a transversal, the corresponding angles are congruent.

so angle 1 and angle 3 are equal:

20x+60=30x+20

60-20=30x-20x

40=10x

x=40/10=4

angle 1 = 20(x)+60

angle 1=20(4)+60=140 degrees

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step-by-step explanation: