Robert Recorde, The designer of 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 ofwel which the first is made thus + and betokeneth more: the other is thus made − and betokeneth lesse." Voor https://sapphire-mushroom-mz3s53.mystrikingly.com/blog/5-eenvoudige-feiten-over-boren-in-wrapfolie-beschreven