Question

who ever solve all these questions i will mark them as the brainliest.
do all sums on a paper.

Hurry up​

Answer 1

Answer:

2) (i) (a-4)(a+4).

By using formula (a-b)(a+b)=a²-b² where a=a & b=4.

(a-4)(a+4)=(a)²-(4)².

=a²-16.

(ii) (2m-5)(2m+5).

By using formula (a-b)(a+b)=a²-b² where a=2m & b=5.

(2m-5)(2m+5)=(2m)²-(5)².

=4m²-25.

(iii) (m+3)(m-3)(m²+9).

(m+3)(m-3)

By using formula (a+b)(a-b)=a²-b² where a=m & b=3.

(m+3)(m-3)=(m)²-(3)².

=m²-9.

(m²+9)(m²-9).

By using formula (a+b)(a-b)=a²-b² where a=m² & b=9.

(m²+9)(m²-9)=(m²)²-(9)².

=m⁴-81.

(iv) (a+bc)(a-bc)(a²+b²c²).

(a+bc)(a-bc).

By using formula (a+b)(a-b)=a²-b² where a=a & b=bc.

(a+bc)(a-bc)=(a)²-(bc)².

=a²-b²c².

(a²+b²c²)(a²-b²c²).

By using formula (a+b)(a-b)=a²-b² where a=a² & b=b²c².

(a²+b²c²)(a²-b²c²)=(a²)²-(b²c²)².

=a⁴-b⁴c⁴.

3) (i) 107×93.

(100+7)(100-7).

(a+b)(a-b)=a²-b² where a=100 & b=7.

(100+7)(100-7)=(100)²-(7)².

=10000-49.

=9951.

(ii) 30.8×29.2.

(30+0.8)(30-0.8).

(a+b)(a-b)=a²-b² where a=30 & b=0.8.

(30+0.8)(30-0.8)=(30)²-(0.8)².

=900-0.64.

=899.36.

Sorry I didn't understand other problems.

I think this is your answer.