Question

Section (A)
1. Multiply
0.004x1.2
2x11
2. Simplify without actual multiply (using formula)102x98
3. Find the area of a square whose perimeter is 16 cm
4. How much paper is used to make a cube of side 5cm.
5. 1m = 10cm3
6.73-*+
7. Factorize-x2 - 4x - 12
​

Answer 1

2. 102x 98

=[100+2][100-2]

=100^2-2^2

=10000-4

=9996

1.0.004 x1.22x11

=0.056386

3. perimeter of square=4x side 16= 4x side

side=16/4

side=4

area of square = side^2

area of square = 4^2

=16 cm

4. total surface area of cube =

6side^2

= 6x5^2

=6x 25

= 150 cm

I cannot understand the 5 &6 question

7. x^2 - 4x -12

=[ x- 2][ x+6]