Senior-secondary mathematics task 110: The roots of x² − 9x + 20 = 0 are r and s. Enter r+s.
By Vieta’s formula, the sum of the roots equals the coefficient 9.
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By Vieta’s formula, the sum of the roots equals the coefficient 9.
Subtract 4 from both sides and divide by 5: x = (59-4)/5 = 11.
Percentage=(14/29)×100=48.28.
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Use the circle-area formula A = πr². Substituting r = 3 gives A = π × 3² = 9π.
Rewrite the value using base 3: 27 = 3^3. Matching exponents gives x = 3.
The dot product is 2×2+6×4=28.
An antiderivative is 2/2 x²+5x. At x=3, the value is 24.0.
f′(x)=15x²+8x. Substituting x=2 gives 76.
The coordinate differences are 3 and 4, so the distance is √(3²+4²)=5.
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There are 6 favourable outcomes out of 12 equally likely outcomes, so P(red)=6/12.
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The sum is n(n+1)/2=21, so the mean is 21/6.
aₙ=a₁+(n−1)d=2+(14−1)×4=54.