Answer:
Correct option: A
Step-by-step explanation:
The angle BDC inscribe the arc mBC, so we have that:
mBDC = (1/2) * mBC
mBDC = (1/2) * 118 = 59°
From the secants relation in a circle, we have that:
mA = (1/2) * (mBC - mDE)
35 = (1/2) * (118 - mDE)
70 = 118 - mDE
mDE = 48°
The sum of the arcs is 360°, so we have:
mBC + mCD + mDE + mBE = 360
118 + mCD + 48 + 76 = 360
mCD = 360 - 118 - 48 - 76 = 118°
The angle mCBD inscribes the arc mCD, so we have:
mCBD = (1/2) * mCD = (1/2) * 118 = 59°
The angles mCBD and mBDC are equal, so the triangle is isosceles.
Correct option: A
Answer:
10 cm
Step-by-step explanation:
If we assume that DC is parallel to AB, then triangle DOC is similar to triangle AOB.
However, even with this assumption, there is not enough information in the diagram to solve for DO. We would also need to know the length of CO. Then we could write a proportion:
DO / (DO + 20) = CO / (CO + 24)
Edit: OD is 2 cm shorter than OC. If we call x the length of OD, then the length of OC is x+2.
Putting this into our proportion:
x / (x + 20) = (x + 2) / (x + 2 + 24)
x / (x + 20) = (x + 2) / (x + 26)
Cross multiply:
x (x + 26) = (x + 2) (x + 20)
Distribute:
x² + 26x = x² + 20x + 2x + 40
x² + 26x = x² + 22x + 40
4x = 40
x = 10
So the length of DO is 10 cm.
Answer:
Step-by-step explanation:
first, do 30-2 to get 28. 7-28 is -21. -21/7 is -3
Answer:
its a=bh
Step-by-step explanation:
Answer:
4.25
Step-by-step explanation:
