已知如图,在平面直角坐标系中,A(-1,-3),OB=,OB与x轴所夹锐角是45°(1)求B点坐标(2)判断三角形ABO的形状(3)求三角形ABO的AO边上的高.
(1)过点B作x轴的垂线交x轴与点C,如图所示:那么根据已知条件,所以在
We wear sunglasses to protect our eyes _____________ the sun.
They are________ different sizes, shapes and metals, but they are exactly the same________.
请用正楷字体在下图“下联”空白处补全对联。