20 Determine whether the ordered pairs (1,0) and 6
7.
are solutions of the following equation.
- 4x + 7y = -4
Is (1,0) a solution of - 4x + 7y= - 4?
Yes
Ο Νο
20
Is 6.
7
a solution of - 4x + 7y = - 4?
No
Yes

Answer choices

So the first thing we do is to multiply the top equation by 3. the reason i want to do this is i notice there will be a 6y on both equations and can possibly add/subtract them. so we get 6y = -3x + 27. adding that and the second equation we get 6x = 27-15 which is 12. divide by 6 and we get 2. ∴ x = 2. substituting 2 into the first equation we get 2y = -2 + 9 which is 7. divide by 2 and we get 7/2. ∴ y = 7/2, x = 2.