S=1/2×d1×d2×sina
22=1/2×(x+3)(2x+1)×1/2
2x²+7x-85=0
D=49+680=729=27²
x1=-7-27/4=-17/2
x2=-7+27/4=5
x=5
S=1/2×d1×d2×sina
22=1/2×(x+3)(2x+1)×1/2
2x²+7x-85=0
D=49+680=729=27²
x1=-7-27/4=-17/2
x2=-7+27/4=5
x=5