Robert Recorde, The designer ofwel the equals sign, introduced plus and minus to Britain in 1557 in The Whetstone of Witte:[14] "There be other twee signes in often use of which the first is made thus + and betokeneth more: the other is thus made − and betokeneth lesse." Bij https://holland-dejesus.technetbloggers.de/hoe-wat-kost-wrapfolie-en-welke-is-de-beste-kan-u-tijd-stress-en-geld-besparen