2s-5t=-21,4s+3t=23求解

2s-5t=-21,4s+3t=23求解
2s-5t=-21,4s+3t=23求解

2s-5t=-21,4s+3t=23求解
要过程吗?

s为2，t为5

s=2，t=5

2.84

2s一5t=一21两边同时乘以2得4S一1Ot=一42然后4s一1ot=一42与4s+3t=23相减得一13t=一65解得t=5把t=5代入原式解得s=2