this can be solve by 3 variable equation
let x be the money of luke
y money of rachel
z money of daniel
first equation
x = y + 21
second equation
x = z + 48
third equation
x + y + z = 168
solving simultaneously
x =79
y = 58
z = 31
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To solve the given equation, w need to review some rules:

The given equation is :


⇒⇒⇒⇒ rule (2)

⇒⇒⇒⇒ rule (1) and rule (2)

⇒⇒⇒⇒ rule (3)
removing the nature logarithm from both sides

∴ x = 4
So, the correct answer is option (2) ⇒⇒⇒⇒ x = 4
➻ In a group of 40 people, 27 can speak English and 25 can speak Spanish.
➻ The required number of people who can speak both English and Spanish .
<u>Consider</u> ,
➻ A → Set of people who speak English.
➻ B → Set of people who speak Spanish
➻ A∩B → Set of people who can speak both English and Spanish
➻ n(A∪B) = n(A) + n (B) - n(A∩B)
➻ 40 = 27 + 25 - n (A∩B)
➻ 40 = 52 - n (A∩B)
➻ n (A∩B) = 52 - 40
➻ ∴ n (A∩B) = 12
∴ Required Number of persons who can speak both English and Spanish are <u>12 .</u>
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➻ n(A∪B) = n(A) + n (B) - n(A∩B)
➻ 40 = 27 + 25 - 12
➻ 40 = 52 - 12
➻ 40 = 40
➻ ∴ L.H.S = R.H.S
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Answer:
x = -11
Step-by-step explanation:
Add 9 to both sides of the equation
3 − 9 = −42
3 − 9 + 9 = −42 + 9
Simplify
Add the numbers
3 = −33
Divide both sides of the equation by the same term
3 = −33
3/3 = −33/3
Simplify
Cancel terms that are in both the numerator and denominator
Divide the numbers
= −11