<7 = <5 vertical angles
<5 = <3 alternate interior angles are equal when the lines are parallel
<2 +<3 = 180 straight line ( complementary angles)
3x+20 + <3 = 180
subtract 3x+20 from each side
<3 = 180 -(3x+20)
<3 = 180 -3x-20
<3 =160 -3x
but from above
<3 also = <5 = <7 and <7 = 2x-10
160 - 3x = 2x-10
add 3x to each side
160 = 5x-10
add 10 to each side
170 = 5x
x = 34
substitute in x=34 to find angle 3
<3 = 160 -3x
<3 =160 -3(34)
<3 =58
to find angle 6
<7+<6 = 180
<7 =<3 = 58
58 + <6 = 180
subtract 58 from each side
<6 = 180 -58
<6 = 122
Distance between C and D =sr( (-7 - -10)^2 + (6 - 2)^2) = sr(3^2 + 4^2) = sr(9 + 16) = sr(25) = 5 units
Answer:A
Explanation:
d = √((5 – 0)2 + (2 – 0)2
d = √(25 + 4) = √(29) ≈ 5.385
Since angle COB is the central angle of arc CB, the measure of arc CB = 80 degrees