Can someone help me do these problems.
They make no sense to me
and the teacher didn't explain this part of the homework.
2007-05-29 16:17:51 · 4 answers · asked by Anonymous in Science & Mathematics ➔ Mathematics
Keep these facts in mind.
i. A straight angle has 180°.
ii. An inscribed angle is one-half the subtended arc.
________
1. 8a + 10 = (1/2)260 = 130 || by ii
8a = 120
a = 15°
2. (8a + 10) + (b² + 10) = 180
b² + 10 = 180 - (8a + 10) = 180 - 130 = 50
b² = 40
b = √40 = 2√10°
I'll leave the rest to you.
2007-05-29 16:28:10 · answer #1 · answered by Northstar 7 · 0⤊ 0⤋
31: The tangent line is a 180 degree angle.
the top angle is 180 -(8a+10) degrees
The bottom angle is 180-(b2+10) degrees
The angles could be solved using simultaneous equations, but there's another way:
The top part of the circle is 260 degrees, therefore the bottom part of the circle must include 360-260 degrees.
If we look at the circle, a 90 degree angle from the tangent line would bisect the circle and each half would have 180 degrees. Therefore we can say that for every two degrees in the circle that the chord line transsects, would equal one degree in the lower tangent line angle.
So, (360 - 260) / 2 = ? degrees?
=> (360 - 260) / 2 = b^2 + 10
=> (360 - 260) / 2 - 10 = b^2
=> b = sqrt ((360 - 260) /2 -10)
Then solve for a
8a + 10 = 180 - (b^2 +10)
=> 8a = 180 -10 - b^2 - 10
=> 8a = 160 - b^2
=> a = 20 - (b^2) / 8
The other problems are handled similarly. Northstar provided the correct answers for question 31. Good luck!
2007-05-29 16:43:05 · answer #2 · answered by Dave L 2 · 0⤊ 0⤋
2) a million. Merwin 2. Bryan 3. Jed 4. JB 5. Allen First step: chanced on first place. JB did no longer are available first, and neither did Brian. considering that Allen got here a place after JB, he ought to no longer have been first, same with Jed who got here 2 places after somebody, for that reason leaving in basic terms Merwin to be first. 2nd step: Jed replaced into 2 places under Merwin, who replaced into in first, so Jed is in 0.33. by using fact the 1st and 0.33 spots crammed, in basic terms the fourth and 5th spots stay as consecutive open spots, permitting Allen and JB to take 5th and fourth respectively. finally the final open spot is going to Bryan via potential of removing.
2016-11-23 16:37:49 · answer #3 · answered by beckim 3 · 0⤊ 0⤋
What does 260degrees, 250 degrees etc. written in the question near the circl's boundary mean?
2007-05-29 16:27:30 · answer #4 · answered by Anonymous · 0⤊ 0⤋