Directions : Read the following quadratic equation carefully and answer the…
2022
Directions : Read the following quadratic equation carefully and answer the questions given below.
(i) x × x - 3x - √(4x²) = -6
(ii) y² - √(81y²) = -4 × 5
(iii) (z²√(625z⁶) / 5z³) + (4 × 7) = 39z
(iv) p² - (3 × 5)p = 7 × -(8)
Find the difference between the larger root of equation (iv) and the smaller root of equation (iii).
Answer: D. 7.2 — Equation (iv) becomes p^2 - 15p + 56 = 0, giving roots 7 and 8. The larger root is 8. For equation (iii), the positive-root equation gives 5z^2 - 39z + 28 =…
- A.
10.4
- B.
9.5
- C.
4.3
- D.
7.2
- E.
5.9
Attempted by 10 students.
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Correct answer: D
Equation (iv) becomes p^2 - 15p + 56 = 0, giving roots 7 and 8. The larger root is 8.
For equation (iii), the positive-root equation gives 5z^2 - 39z + 28 = 0, so z = 7 or 0.8.
The smaller root of (iii) is 0.8.
Required difference = 8 - 0.8 = 7.2.