Correct Answer - Option 5 : No relation in x and y or x = y
Given:
I. x2 - 12x + 36 = 0
II. y2 - 7y - 60 = 0
Calculation:
From I
x2 - 12x + 36 = 0
⇒ x2 - 6x - 6x + 36 = 0
⇒ x(x - 6) - 6(x - 6) = 0
⇒ (x - 6)(x - 6) = 0
⇒ x = 6, 6
From II
y2 - 7y - 60 = 0
⇒ y2 - 12y + 5y - 60 = 0
⇒ y(y - 12) + 5(y - 12) = 0
⇒ (y - 12)(y + 5) = 0
⇒ y = 12, -5
Comparison between x and y (via Tabulation)
Value of x |
Value of y |
Relation between x & y |
6 |
12 |
x < y |
6 |
-5 |
x > y |
6 |
12 |
x < y |
6 |
-5 |
x > y |
∴ No relation in x and y or x = y.
Sign Method |
Equation |
Sign |
Remark |
ax2 + bx + c = 0 |
-Ve, -Ve |
Same signs |
ax2 - bx + c = 0 |
+Ve, +Ve |
Same signs |
ax2 + bx - c = 0 |
-Ve, +Ve |
Larger root is negative
smaller root is positive |
ax2 - bx - c = 0 |
-Ve, +Ve |
Larger root is positive
smaller root is negative |