Đáp án:
Đáp án:
Giải thích các bước giải:
1)y=(2m−5)x+3a)Hamsolahambacnhat⇔2m−5≠0⇔m≠52b)HamsoDB⇔2m−5>0⇔m>52HamsoNB⇔2m−5<0⇔m<521)y=(2m−5)x+3a)Hamsolahambacnhat⇔2m−5≠0⇔m≠52b)HamsoDB⇔2m−5>0⇔m>52HamsoNB⇔2m−5<0⇔m<522)XetΔAHC:AH=AC.sin400≈6,23(cm)XetΔAH:BH=AH.cot500≈5,4(cm)2)XetΔAHC:AH=AC.sin400≈6,23(cm)XetΔAH:BH=AH.cot500≈5,4(cm) 3)a)KeAH⊥BCXetΔvAHC:AH=AC.sin500≈26,81(cm)XetΔvAHB:sin600=AHAB⇒AB=AHsin600≈30,96(cm)ApdungDLpytagotrongΔvABC:BC=√AB2+AC2≈46,72(cm)b)SΔABC=12AH.BC≈626,39(cm2)3)a)KeAH⊥BCXetΔvAHC:AH=AC.sin500≈26,81(cm)XetΔvAHB:sin600=AHAB⇒AB=AHsin600≈30,96(cm)ApdungDLpytagotrongΔvABC:BC=AB2+AC2≈46,72(cm)b)SΔABC=12AH.BC≈626,39(cm2)
