samsonhohoho
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One root of the equation x^2 - (r+3)x + 2(r+1) = 0 is twice the other root. Find the two possible values of r. Please show working THANKS!
Quadratic polynomial help! (1 Viewer)
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nightweaver066
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Let the roots be a and 2a.
Sum of roots = 3a = r + 3
Product of roots = 2a^2 = 2(r + 1)
a^2 = r + 1
Simultaneous equations to get possible values of r.
Sum of roots = 3a = r + 3
Product of roots = 2a^2 = 2(r + 1)
a^2 = r + 1
Simultaneous equations to get possible values of r.