Figure 3 shows parallelogram RSTU.Sides R U and S T are horizontal,with S T above,and
slightly to the left of side R U.Diagonal S U,which extends from vertex S at the upper left of the
parallelogram to vertex U at the lower right of the parallelogram,divides the parallelogram into
two triangles,R S U and U S T; and the angle at vertex S into 2 adjacent angles R S U and U S T.The measure of angle R S U is x degrees,and the measure of angle U S T is y degrees
圖3顯示平行四邊形RSTU.邊RU與ST平行,ST在RU上方,并且比RU稍微偏左.連接左上頂點(diǎn)S和右下頂點(diǎn)U的對(duì)角線SU,將平行四邊形劃分為兩個(gè)三角形RSU和UST,并將角劃分為角RSU和UST.角RSU為x度,角UST為y度.