Answer:
The radius of the circle P = 2√10 = 6.325
Step-by-step explanation:
∵ AB is a tangent to circle P at A
∴ (AB)² = BC × BE
∵ BC = 8 , AB = 12 , ED = 6
∵ BE = ED + DC + CB
∴ BE = 6 + CD + 8 = 14 + CD
∴ (12)² = 8 × (14 + DC) ⇒ (12)²/8 = 14 + CD ⇒ CD = (12)²/8 - 14
∴ CD = 4
Join PC and PE (radii)
In ΔBDC and ΔPDE ⇒ ∵ ∠PDC = Ф , ∴ ∠PDE = 180 - Ф
Use cos Rule:
∵ r² = (PD)² + (DC)² - 2(PD)(DC)cosФ
∴ r² = 16 + 16 - 32cosФ = 32 - 32cosФ ⇒ (1)
∵ r² = (PD)² + (DE)² - 2(PD)(DE)cos(180 - Ф) ⇒ cos(180 - Ф) = -cosФ
∴ r² = 16 + 36 + 48cosФ = 52 + 48cosФ ⇒ (2)
∵ (1) = (2)
∴ 32 - 32 cosФ = 52 + 48cosФ
∴ 32 - 52 = 48cosФ + 32cosФ
∴ -20 = 80cosФ
∴ cosФ = -20/80 = -1/4
∴ r² = 32 - 32(-1/4) = 32 + 8 = 40
∴ r = √40 = 2√10 = 6.325
A1. 12 i.e option D
A2. 3n-7 i.e option A
A3. -6n+20 i.e option D
A4. -70 i.e option C
Step-by-step explanation:
aₙ = a₁ + (n - 1) × d
aₙ = the nᵗʰ term in the sequence
a₁ = the first term in the sequence
d = the common difference between terms
Using the above formula to solve the first part, we have :
For the second part, we have :
For the third part, we have :
For the fourth part, we have :
Answer:
The answer is 5.75
Step-by-step explanation:
I used desmos
Answer:
We just add numerators and rewrite denominator.
Adding unlike dominators:
We need to find the same denominators. You need to find the least common multiple (LCM) of the two denominators.
Step-by-step explanation:
You mean unlike denominators and like denominators.
Adding like dominators: We just add numerators and rewrite denominator :
Example : 
Adding unlike dominators:
We need to find the same denominators. You need to find the least common multiple (LCM) of the two denominators.
For example :
LCM for 5 and 4 is 20 : Now, divide by 5 and multiply by 1 for first fraction. 20 divide by 4 and multiply by 3 :
Answer:
y = -4/3x + 6
Step-by-step explanation:
1. 3y - 4x + 3y = 18 - 3y
2. 4x = -3y + 18
3. 18 - 4x = -3y + 18 - 18
4. <u>-</u><u>3</u><u>/</u><u> </u><u>-3y = 4x - 18</u><u> </u><u>/</u><u>3</u>
5. y = -4/3x + 6
