A rare strike by Laurent Koscielny opened the scoring at the Emirates Stadium before Mesut Ozil netted for the 10th time this season and Olivier Giroud sealed victory with his 21st goal of the campaign to boost the Gunners' hopes of a 17th successive term in Europe's premier club competition. (Agencies)
Arsene Wenger's side now require just one more victory from their final two league matches against either West Bromwich Albion or Norwich City to book their spot.
"We had some problems at the start of the game, trying to find our way through the defence. When we found an opening we became stronger," Gunners boss Wenger said.
In truth, visitors Newcastle had goalkeeper Tim Krul to thank for keeping the scoreline respectable as Alan Pardew, back on the touchline after a seven-game absence due to suspension, saw his side suffer a sixth successive league defeat -- the north-east club's worst run in the English top flight since the 1986/87 season.
"It was tough for us tonight," said Pardew, whose side remain ninth in the table. "We dug in, worked hard and tried to offer a threat but they (Arsenal) were too good. We need to focus on finishing in the top 10. We'll be really up for it and hopefully we'll get a win," Pardew added.
The Englishman added: "We're going to work hard in the summer to make sure we have a team that can make this city proud. I'm looking at the job as a long-term opportunity for myself. That's how you have to focus."
While followers of fifth-placed Everton were cheering on Newcastle in the hope they could do them a favour, the blue half of Merseyside would be disappointed as Arsenal, with the FA Cup final against Hull City at Wembley on May 17 confined to the back of their minds, dominated throughout.
Arsenal, with Aaron Ramsey and Ozil back in the groove after building up their match-fitness following injuries, looked slicker and sharper and it was little surprise when the north London side took the lead in the 26th minute.
Moussa Sissoko needlessly pulled down Giroud 40 yards out from goal and Santi Cazorla's pin-point delivery allowed Koscielny to nip in at the back post and flick home for his second goal of the season.
Arsenal almost doubled their advantage two minutes later when Lukas Podolski saw his effort from an acute angle on the left side of the area turned around the post by Krul's legs.
Krul came to the rescue once again on the half-hour mark when the Dutch 'keeper produced an excellent save to keep out Podolski's header from point-blank range. But the second goal Arsenal had been threatening arrived three minutes before the interval.
Giroud broke Newcastle's offside trap to latch onto Mikel Arteta's through ball and the striker was twice denied by Krul only for Ozil to tap home the rebound. Replays did show that Ozil was in an offside position when he converted, but the goal stood.
Arsenal maintained the pressure early in the second period, Cazorla hitting a volley over the crossbar and Bacary Sagna heading over.
Newcastle, whose supporters began to turn on manager Pardew, could have halved the deficit in the 58th minute when Yoan Gouffran raced clear onto Loic Remy's pass, but his shot was straight at Gunners goalkeeper Wojciech Szczesny.
The misery continued for Pardew as the hosts scored a simple third goal when the unmarked Giroud headed home from six yards from Ozil's left-wing cross.
That sparked a series of growing chants from the away section of the ground such as "Next excuse, Pardew?" and "Pardew Out" as the pressure increased on the Newcastle manager.
But, for Wenger and Arsenal, this was a good job, well done as they took another major step towards Champions League qualification.
A rare strike by Laurent Koscielny opened the scoring at the Emirates Stadium before Mesut Ozil netted for the 10th time this season and Olivier Giroud sealed victory with his 21st goal of the campaign to boost the Gunners' hopes of a 17th successive term in Europe's premier club competition.