Question

1 .

a. Solve by elimination method.
x+y = 6 ; 2x - y = 3

b. Solve by substitution method.
2x - y = 7 , y = 3x

c. Solve
x^2 +(1 /16 ) = x / 2

2 . Factorize
a. a^2 - 2a - 2b - b^2
b. a^4 - 3a^2 + 1

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Answer 1

Explanation:

a .

x + y = 6

+

2x - y = 3

3x = 9

3x/3 = 9/3

x = 3

x + y = 6

y = 6 -x

y = 6 - 3

y = 3

b.

2x - y = 7

+

y = 3x

2x = 3x + 7

2x - 3x = 7

x = -7

y = 3x

y = 3(-7)

y = -21

c.

`{x}^(2) + (1)/(16) = (x)/(2)`

`{x}^(2) + (1)/(16) - (x)/(2) = 0`

`16( {x}^(2) - (x)/(2) + (1)/(16) ) = 0`

`16 {x}^(2) - 8x + 1 = 0`

`(4x - 1)(4x - 1) = 0`

`x = (1)/(4)`

2.

a.

`{a}^(2) - 2a - 2b - {b}^(2)`

`a(a - 2) - b(b + 2)`

Answer 2

1a. x=3 y=3

1b. x=-7 y=-21

1c. x=¼

2a. a(a-2)-b(2+b)

2b. a²(a²-3)+1