Answer:
2x + 2y = 10
(d) is the correct option.
Step-by-step explanation:
The given set of equations are 3x + y = 19 and x + 3y = 1
Now, Let us try and find the values of x and y from these equation.
3x + y = 19 ...... (1)
x + 3y = 1 ......... (2)
Multiple equation (2) by 3 and subtract from (1), we get
3x + y - 3(x+ 3y) = 19 - 3(1)
or, 3x + y - 3x - 9y = 19 -3
or, -8y = 16
or, y = 16/-2 = -2
So, y = -2
Put this value in (1), we get
3x - 2 = 19
or, 3x = 19 +2 = 21 ⇒ x = 21/3 = 7
So, x = 7 and y = -2 is the solution of the given set of equations.
So, 2x + 2y = 2(7) + 2(-2) = 14 - 4 = 10
⇒ 2x + 2y = 10
(d) is the correct option.
