Question

x^2 - ax + 20 = o

repedee va rog mult

Answer 1

$4 {}^{2} - 4a + 20 = 0 \\ - 4a = - 20 - 16 \\ - 4a = - 36 \\ a = - 36 \div ( - 4) = 9 \\ x { }^{2} - 9x + 20 = 0 \\ (x - 4).( x - 5) \: are \: solutii \: x = 4 \: si \: x = \: \ 5 \\ mg. = \sqrt{4.5} = \sqrt{4} . \sqrt{5} = 2. \sqrt{5}$