Question
The sum of the ages of a father and his son is 50 years.
After 10 years, the father will be four times as old as the son. What are their current ages?Solution
Let the present age of the father be F and the present age of the son be S. According to the question: F + S = 50 (Equation 1). After 10 years, F + 10 = 4(S + 10) (Equation 2). Substitute Equation 1 into Equation 2: F = 50 - S. 50 - S + 10 = 4(S + 10). 60 - S = 4S + 40. 60 - 40 = 4S + S. 20 = 5S. S = 4. Substitute S = 4 into Equation 1: F + 4 = 50, F = 46. Father's age = 46 years, Son's age = 4 years. Correct answer: a. Father is 46, son is 4Â Â Â Â Â Â Â Â
I. 6 y² + 11 y – 7= 0
II. 21 x² + 5 x – 6 = 0
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I. 8x² + 2x – 3 = 0
II. 6y² + 11y + 4 = 0
I. 2x² - 15x  + 13 = 0
II. 3y² - 6y + 3 = 0
I. 2x² - 7x + 3 = 0
II. 8y² - 14y + 5 = 0
Solve the quadratic equations and determine the relation between x and y:
Equation 1: 3x2 + 6√7x - 315 = 0    Â
E...
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II. 30y² + 17y – 21 = 0
I. 195x² - 46x - 21 = 0
II. 209y² + 7y - 12 = 0
I. 2y2 - 37y + 143 = 0
II. 2x2 + 15x – 143 = 0
I. 22x² - 97x + 105 = 0
II. 35y² - 61y + 24 = 0
