5х^2+4х-9<или=0 решите неравенство

Question

5х^2+4х-9<или=0 решите неравенство<br>

Answer 1

5x²+4x-9≤0
5x²+9x-5x-9≤0
5x²+9x-(5x+9)≤0
x(5x+9)-(5x+9)≤0
(x-1)(5x+9)≤0
5(x-1)(x+1.8)≤0
x∈[-1.8; 1]