12sinx + 5cosx +13 = 0
√(12²+5²)=√(144+25)=√169=13 13(12/13*sinx+5/138cosx)=-13 12/13*sinx+5/13*cosx=-1 sin(x+a)=-1 sina=5/13 U cosa=12/13 x+a=-π/2+2πn x=-a-π/2+2πn,n∈z x=-arcsin5/13-π/13+2πn,n∈a