1,2 : 36 ≈ 0,03
1234567890-=
∠BDA=45°; ∠BDC=43°; ∠ADC=∠BDA+∠BDC=88°
∠BAD=∠ADC=88<span>° трапеция равнобедренная
</span>∠АВС=(360-∠BAD-<span>∠ADC)/2=360</span>°-2*88=184/2=92°
15х-(-3 х-(19-18 х))+3х=х+90+2х
15х-(-3х-19+18х)+3х=х+90+2х
15х-3х+19-18х+3х=х+90+2х
15х-3х-18х+3х-2х-х=90-19
-6х=71
х=-71/6
х=11 цел 5/6