Question

if (a+b+c)^2=a^2+b^2+c^2+2ab+2bc+2ca then evaluate (9x + 2y +7)^2 tell fast ⏩​

Answer 1

refer the above image

hope this is helpful

Answer 2

Step-by-step explanation:

(9x+2y+7)^2

(9x)^2+(2y)^2+(7)^2+2*9x*2y+2*2y*7+2*7*9x

81x^2+4y^2+49+36xy+28y+126x