In each of these questions, two equations (I) and (II) are given.You have to solve both the equations and give answer.
1.
I. [latex]x^{3}[/latex] – 4913 = 0
II. [latex]y^{2}[/latex] – 361 = 0
A. if x ≤ y
B. if x = y or relationship between x and y can't be established
C. if x ≥ y
D. if x ≥ y
E. if x ≤ y
Answer: Option B
Explanation:
I. [latex]x^{3}[/latex] – 4913 = 0
or, [latex]x^{3}[/latex] = 4913
x = 17
II. [latex]y^{2}[/latex] = 361
or, y = ± 19
While comparing the values of x and y, one root value of y lies between the root values of x
2.
I. [latex]x^{2}[/latex] = 361
II. [latex]y^{3}[/latex] = 7269 + 731
A. if x ≤ y
B. if x ≥ y
C. if x ≥ y
D. if x ≤ y
E. if x = y or relationship between x and y can't be established
Answer: Option A
Explanation:
I. [latex]x^{2}[/latex] = 361
x = ± 19
II. [latex]y^{3}[/latex] = 7269 + 731
[latex]y^{3}[/latex] = 8000
y = 20
x ≤ y
3.
I. 15[latex]x^{2}[/latex] + x – 6 = 0
II. 5[latex]y^{2}[/latex] – 23y + 12 = 0
A. if x ≥ y
B. if x ≤ y
C. if x ≥ y
D. if x ≤ y
E. if x = y or relationship between x and y can't be established
Answer: Option B
Explanation:
I. 15[latex]x^{2}[/latex] + x – 6 = 0
15[latex]x^{2}[/latex] + 10x – 9x – 6 = 0
5x (3x + 2) – 3 (3x + 2) = 0
(5x – 3) (3x + 2) = 0
x = [latex]\frac{3}{5}[/latex], –[latex]\frac{2}{3}[/latex]
II. 5[latex]y^{2}[/latex] – 23y + 12 = 0
5[latex]y^{2}[/latex] – 20y – 3y + 12 = 0
5y (y – 4) – 3 (y – 4) = 0
(y – 4) (5y – 3) = 0
y = 4, [latex]\frac{3}{5}[/latex]
x ≤ y
4.
I. [latex]x^{3}[/latex] – 2744 = 0
II. [latex]y^{2}[/latex] – 256 = 0
A. if x ≥ y
B. if x ≤ y
C. if x ≥ y
D. if x ≤ y
E. if x = y or relationship between x and y can't be established
Answer: Option E
Explanation:
I. [latex]x^{3}[/latex] – 2744 = 0
[latex]x^{3}[/latex] = 2744
x = 14
II. [latex]y^{2}[/latex] – 256 = 0
[latex]y^{2}[/latex] = 256
y = ± 16
While comparing the values of x and y, one root value of x lies between the root values of y.
5.
I. [latex]x^{2}[/latex] – 8x – 20 = 0
II. 3[latex]y^{2}[/latex] – 60y + 297 = 0
A. if x ≥ y
B. if x ≤ y
C. if x ≥ y
D. if x ≤ y
E. if x = y or relationship between x and y can't be established
Answer: Option B
Explanation:
I. [latex]x^{2}[/latex] – 8x – 20 = 0
[latex]x^{2}[/latex] – 10x + 2x – 20 = 0
x (x – 10) + 2 (x – 10) = 0
(x – 10) (x + 2) = 0
Then, x = + 10 or x = – 2
II. 3[latex]y^{2}[/latex] – 60y + 297 = 0
[latex]y^{2}[/latex] – 20y + 99 = 0 [Dividing both sides by 3]
[latex]y^{2}[/latex] – 11y – 9y + 99 = 0
y (y – 11) – 9 (y – 11) = 0
(y – 11) (y – 9) = 0
Then, y = + 11 or y = + 9
So, when x = + 10, x y for y = + 9
And when x = – 2, x ≤ y for y = + 11 and x ≤ y for y = + 9
So, we can observe that one root value of x lies between the root values of y. Therefore, the relation between x and y can't be determined.