Question

Select the correct

What is the solution to this system of equations?
3x + y = 17
x + 2y = 49
O A.It has no solution.
OB. It has infinite solutions.
O C. It has a single solution: x = 15, y = 17.
OD. It has a single solution: x = -3, y = 26.

Answer 1

It's D because

3x + y = 17
-3x -3x

Y= -3x+17

So you substitute in the x+2y=49

x+2(-3x+17)=49
-5x + 34 = 49
-5x + 34 = 49
-34 -34

-5x = 15

X = -3

And now we find y

Y = -3x+ 17
Y= -3(-3) + 17

Y=26

(-3, 26)