Because there are 4 inside angles the sum of the four angles must equal 360 degrees.
Add the angles to equal 360:
4x + 3x + 2x + 3x = 360
Simplify:
12x = 360
Solve for x by dividing both sides by 12:
x = 360 /12
x = 30
Now you have x, solve for each angle:
ABC = 4x = 4 x 30 = 120 degrees.
BCD = 3x = 3 x 30 = 90 degrees.
CDA = 2x = 2x 30 = 60 degrees.
DAB = 3x = 3 x 30 = 90 degrees.
C. It's important to know that a four sides figure needs the inside angles when added together need to equal 360 degrees.
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Answer:
B. 50
Step-by-step explanation:
The alternate interior angles at transversal t across parallel lines AB and CD will be congruent.
2x +40 = x +90
x = 50 . . . . . . . . . . . subtract x+40
The value of x is 50.
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<em>Check</em>
2x+40 = 2×50 +40 = 140
x+90 = 50 +90 = 140 . . . . so the obtuse angles are congruent, as they should be
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<em>Additional comment</em>
The lines AB and CD are not shown as being parallel. We have to assume they are, or we cannot work the problem.
Check the picture below.
now, since we know what "f" is, let us use the CNT triangle with the small COR one.
4*15=60
19*7=133
133-60=73
the shaded area is 73
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