Becuase 80 is the same as 8 but has an extra 0 at the end (which makes it 80) and same for 20 to 2. 8 + 2 = 10 (now add a zero at the end). The answer should be 100.
c
All the information you need is in the quadratic trinomial ... Read from right to left:
Find factors of 49 which ADD (+) to give 14.
These will be 7
and
7 because:
7
×
7
=
49
and
7
+
7
=
14
The + sign shows that the signs in the brackets will be the SAME, the minus (-) shows that they will be negative:
(
x
−
7
)
(
x
−
7
)
=
(
x
−
7
)
2
