ANSWER: <em><u>D. Icosahedron</u></em>
Answer:
m∠CFD is 70°
Step-by-step explanation:
In the rhombus
- Diagonals bisect the vertex angles
- Every two adjacent angles are supplementary (their sum 180°)
Let us solve the question
∵ CDEF is a rhombus
∵ ∠E and ∠F are adjacent angles
→ By using the second property above
∴ ∠E and ∠F are supplementary
∵ The sum of the measures of the supplementary angles is 180°
∴ m∠E + m∠F = 180°
∵ m∠E = 40°
∴ 40° + m∠F = 180°
→ Subtract 40 from both sides
∵ 40 - 40 + m∠F = 180 - 40
∴ m∠F = 140°
∵ FD is a diagonal of the rhombus
→ By using the first property above
∴ FD bisects ∠F
→ That means FD divides ∠F into 2 equal angles
∴ m∠CFD = m∠EFD =
m∠F
∴ m∠CFD =
(140°)
∴ m∠CFD = 70°
The most important part of this question is understanding the words of the problem. The trick lies in the words of the problem. Once the web of words is simplified, the problem becomes very easy. The main thing is converting the words into numbers.
Let us assume the unknown number = x
Then from the question we get
(x/4) = (x/5) + 1
(x/4) - (x/5) = 1
(5x - 4x)/20 = 1
x/20 = 1
x = 20
So the unknown number is 20
36 different outcomes.
6 x 6 = 36
Each side of dice 1 could have a counter match of 6 possibilities x 6