Answer:
1.D
2.D
3.B
4.A
5.A
Explanation:
1.We are given that two equations


Adding two equations then we get


Substitute e=5 in equation one then we get



Hence, the ordered pair as (10, 5).
Therefore,Option D is true.
2.We are given that two equations
Equation S:

Equatin T:

Using substitution method
Substitute the value of y from equation one in equation second then we get

Therefore, option D is true.
3.We are given that two equations
Equation C :

Equation D

The two equations can be written as








Therefore, system of equations have no solution
Hence, option B is true.
4.We are given that two equations


Using substitution method
Substitute value of y from equation second in equation one
Then we get




Substitute the value of x in equation second then we get



Hence, option A is true.
5.We are given that two equations


Using substitution method
Substitute value of y from equation one in second equation then we get

Hence, option A is true.