Question

Sylvain spent a total of 18 hours on English and math homework over the last 3 weeks. He spent twice as much time on English than on math. Let x represent the number of hours spent on English and y represent the number of hours spent on math.

x + y = 18. x = 2 y.

What is the solution of the system of equations?
(12, 6)
(6, 12)
(9, 9)
(15, 3)

Answer 1

x = 2y

2y + y = 18 x + y = 18
3y =18 x + 6 = 18
y = 6 x = 12


(12,6)

Answer 2

12, 6

Explanation:

we have two equations

x + y = 18 .... . (i)

and x = 2y .... .(ii)

substituting the value of x from eq. (ii) in eq. (i)

2y + y = 18

3y = 18

y = 6

putting this value if y in equation (ii) to get x

x = 2 × 6

= 12

therefore,

(12, 6) is the solution to the system of equations