Solve the following system of equations by linear combination:

2d - e = 7 d + e = 5

a. The solution is (4, 1).

b. There are an infinite number of solutions.

c. The solution is (3, - 1).

d. There is no solution.

The solution is (4, 1).

Step-by-step explanation:

For the first multiply the second equation by - 1 then add them together.

4x + y = 5

-1 (3x + y = 3)

4x + y = 5

-3x - y = - 3

x=2

Plug that in and you get - 3 for y

Answer is (2,-3)

For the second, just add them

2d - e = 7

d + e = 5

3d=12

d=4

Plug that into either equation and e is 1

The solution is (4, 1).