Question

Which ordered pair (a, b) is a solution to the given system of linear equations?

A (1, 7)
B (3, 1)
C (11, –23)
D (23, –11)

Answer 1

11,-23 is the answer I plugged in the two number as a and b and I got 33+(-23)=10 and -44+ (46)= 2

Answer 2

C. (11,-23)

Explanation:

The given equations are

`3a+b=10`.....................equation 1

`-4a-2b=2`...................equation 2

Multiply first equation by 2

`6a+2b=20`

Now add this new equation to 2nd equation

`6a-4a +2b-2b = 20+2`

`2a = 22`

Divide both sides by 2

`a=11`

We got a=11 , plug this value in anyone equation

3(11)+b=10

`33+b=10`

Subtract 33 from both sides

`b=-23`

So solution is (a,b) = ( 11,-23)