Verified answer

Ответ:

[tex]\bf0,49t^2+2,1st+2,25s^2[/tex]

Объяснение:

[tex]\displaystyle (0,7t+1,5s)^2=(0,7t)^2+2*0,7t*1,5s+(1,5s)^2=\bf0,49t^2+2,1st+2,25s^2[/tex]

формула: [tex]\displaystyle\boxed{\Large\sf(a+b)^2=a^2+2ab+b^2}[/tex]