Answer:

Step-by-step explanation:
Recall the form of the difference of squares.

Now let's apply it to your numbers:

Simplify:

Answer:
X=SMALL BOX.
Y=LARGE BOX
THEREFORE,X+Y=21
X=21-Y
THEREFORE,25(21-Y)+70Y=1110 POUNDS
525-25Y+70Y=1110
525+45Y=1110
45Y=1110-525
45Y=585
Y=585/45
Y=13 .
Therefore,13 large box and8 small box..
Answer:
x=9
Step-by-step explanation: