The sum of the ages of A and B is (3x + 10) years. 5 years ago, the ratio of their ages was 4:5. Find the present age of A, if B is 4 years older than A.
Solution: Let A's age be y years and B's age be y + 4 years. According to the given condition, y + (y + 4) = 3x + 10 2y + 4 = 3x + 10 2y = 3x + 6 y = (3x + 6) / 2 5 years ago, the ratio of their ages was 4:5. So, (y - 5) / (y + 4 - 5) = 4/5 (y - 5) / (y - 1) = 4/5 Cross-multiply and solve for y: 5(y - 5) = 4(y - 1) 5y - 25 = 4y - 4 y = 21 Present age of A = 21 years
I. 2y² - 3y – 14 = 0
II. 3x² - 7x + 4 = 0
I. 40 x² - 93 x + 54 = 0
II. 30 y² - 61 y + 30 = 0
I. 2x2- 5x - 33 =0
II. 2y2+ 5y - 25 = 0
I. p²= ∛1331
II. 2q² - 21q + 55 = 0
I. 3x2 – 17x + 10 = 0
II. y2 – 17y + 52 = 0
I. 6x2 + 19x + 10 = 0
II. y2 + 10y + 25 = 0
I. x2 + 91 = 20x
II. 10y2 - 29y + 21 = 0
I. 10x2 + 33x + 9 = 0
II. 2y2 + 13y + 21 = 0
A and B are the roots of equation x2 - 13x + k = 0. If A - B = 5, what is the value of k?
I. x2 – 12x + 32 = 0
II. y2 + y - 20 = 0
