root x+5+ root x-16/root x+5- root x-16=7/3 prove x=20
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proved
Step-by-step explanation:
root x+5+ root x-16/root x+5- root x-16=7/3
√ x + 5+√x-16/√ x+5- √ x-16 = 7/3
√ x + 5+√x-16 ÷ √ x+5 - √ x-16 = 7/3
multiply and divide by the conjugate of the LHS
{√(x+5) + √(x-16)}² ÷ (x+5) - (x-16)
2x -11 + 2√(x² - 11x-80) = 21×7/3 = 49
2√(x² - 11x-80 )= 60-2x
x² - 11x-80 = (30- x)² = x² - 60x +900
49 x = 980
x = 980 ÷ 49
x = 20
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