Question 777446
10w^2-4w+3w^2+18w


(10w^2+3w^2)+(-4w+18w)


(13w^2)+(14w)


<font color="red">13w^2+14w</font>


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8(s-t)+16(t-s)


8s-8t+16t-16s


(8s-16s)+(-8t+16t)


(-8s)+(8t)


<font color="red">-8s+8t</font>