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Find two consecutive odd positive integers, sum of whose squares is 290 |
Answer» Answer:11 and 13 Given:
To Find:
Solution:The integers are odd consecutive, so, there difference should be 2. let the first integer = x The second integer = x + 2 According to the question ⟹ ( x )² + ( x + 2)² = 290 By opening the whole squares, ⟹ x² + x² + 4X + 4 = 290 ⟹ x² + x² + 4x + 4 - 290 = 0 ⟹ 2x² + 4x - 286 = 0 ⟹ 2( x² + 2x - 286) = 0 ⟹ x² + 2x - 286 = 0 By splitting the middle term, ⟹ x² + 13x - 11x - 143 = 0 ⟹ x ( x + 13 ) - 11 ( x + 13 ) = 0 ⟹ ( x + 13 ) ( x - 11 ) = 0 Now, ⟹ (x + 13) = 0 ⟹ x = -13 - 13 is not possible as the integers should be positive OR ⟹ (x - 11 ) = 0 ⟹ x = 11 First integer = x = 11 Second integer = (x + 2) = 13 11 and 13 are the integers. Verification:Sum of their squares should be 290 ⟹ (11)² + (13)² ≟ 290 ⟹ 121 + 169 ≟ 290 ⟹ 290 = 290 LHS = RHS verified ! |
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