Synchronous detection of eighth grade mathematics (Zhejiang Education Edition) in the second semester of 20 10 school year —— An answer from SMJ (1678)
1— 10 acbcdbbdc( 1 1)。 Root number 5/5 (12). 50 ( 13).75 ( 14).False (65438)。 1(16) 54 (17) 7 (18) 2.5 (19) 8+2 radical 3 (20) K=8, x =-/kloc-0. 65438+AF = AB ∴∠ AFB = ∠ ABF = 30 ∴∠ BFE = ∠ FBC = 90 ∠ FEC = ∠ BCE = 90 ∴ parallelogram BCEF is a rectangle (23