Question

Solve the following system of equations by linear combination:

3d – e = 7

d + e = 5



The solution is (3, 2).

The solution is (2, –1).

There is no solution.

There are an infinite number of solutions.

Answer 1

3d - e =7
d + e = 5
-------------
4d / = 12
d=12:4
d=3

3+e=5
e=5-3
e=2
the solution is (3,2)