Question

The pair of equation 2x - 5 y + 4 = 20 and 2x + y - 8 = 20 has.
(a) a unique solution,
(b) exactly two solution,
(c) infinitely many solutions,
(d) no solution
please solve this question with solution.​

Answer 1

Step-by-step explanation:

Correct option is

A

Unique solutions, x=2 and y=1

Given pair of equations are:

2x+y=5 ...(i)

and 3x+2y=8 ...(ii)

a

2

a

1



=

b

2

b

1

(

a

2

a

1

=

3

2

,

b

2

b

1

=

2

1

)

Here, we have a. unique solution.

By cross multiplication, we have

⇒

{(1)(−8)−(2)(−5)}

x

=

{(−5)(3)−(−8)(2)}

y

=

{(2)(2)−(3)(1)}

1

⇒

(−8+10)

x

=

(−15+16)

y

=

(4−3)

1

⇒

2

x

=

1

y

=

1

1

⇒

2

x

=

1

1

and

1

y

=

1

1

⇒x=2 and y=1

Answer 2

Answer:

unique solution

Step-by-step explanation:

a1÷a2 is not equal to b1÷b2 =it is unique solution