3. Simplify each of the following:
(i) 175 x 175 + 2 x 175 x 25 + 25 x 25 (ii) 322 x 322 – 2 x 322 x 22 + 22 x 22
7.83 x 7.83 - 1.17 x 1.17
(iii) 0.76 x 0.76 + 2 x 0.76 x 0.24 +0.24 x 0.24
Answers
in first we will use the formula of a plus b whole square is equal to a square + 2 a b + b square so it is given a square + 2 a b + b square so we will make the answer as a + b whole square then our solution will become easier.
(a+b)^2
(175+25)^2
(200)^2
40000
so we will do same as we have done in the first question ok we will use the formula of a plus b whole square is equal to a square minus 2 a b + b square
(322-22)^2
(300)^2
90000
it is same we have done in first question a + b whole square is equal to a square + b square + 2 Ab
(0.76+0.24)^2
(1)^2
1
1). 175 × 175 + 2 × 175 × 25 + 25 × 25
= (175)² + 2(175)(25) + (25)²
= (175 + 25)²
Now,
Assume :-
x = 175 and also y = 25
So,
Using Identity :-
(x + y)² = x² + y² + 2xy
So,
= (200)²
= 40000
2). 322 × 322 - 2 × 322 × 22 + 22 × 22
= (322)² - 2 × 322 × 22 + (22)²
= (322 - 22)²
Assume :-
x = 322 and also y = 22
So,
Using Identity :-
(x - y)² = x² + y² - 2xy
So,
= (300)²
= 90000
3). 0.76 × 0.76 + 2 × 0.76 × 0.24 + 0.24 × 0.24
= (0.76)² + 2 × 0.76 × 0.24 + (0.24)²
= (0.76 + 0.24)²
Assume :-
x = 0.76 and also y = 0.24
So,
Using Identity :-
(x + y)² = x² + y² + 2xy
So,
= (1.00)²
= 1