Find the squares of the following numbers; (I)515               (ii)   580               (iii)   509

Explanation

(1)Square of `515` is `(500+15)^2=(515)^2`
using identity `(a+b)^2=a^2+b^2+2ab`we have,
`=(500)^2+(15)^2+2xx500xx15`
`=250000+225+15000`
`=265225`
(ii)`580^2=(600-20)^2`
`=(600)^2+(20)^2-2xx600xx20`
`=360000+400-24000`
`=336400`
(iii)`(509)^2=(500+9)^2`
`=(500)^2+(9)^2+2xx500xx9`
`=250000+81+9000`
`=259081`