One equation in a system of equations is y = 4x + 5. Which equation below would have to be the second equation so that the system has (1, 9) as its only solution?

Question

One equation in a system of equations is y = 4x + 5. Which equation below would have to be the second equation so that the system has (1, 9) as its only solution?

Answer 1

y = 4x + 5

(1,9) is a solution

9 = 4(1) + 5 = 4+5

9=3(1) + 6 = 3+6

y=3x +6 is a 2nd equation that intersects the 1st equation at (1,9)

9=2(1)+7 = 2+7

y = 2x +7 is another 2nd equation that intersects at the same solution (1,9

y= 9 is another 2nd equation

9=-(1)+10 10-1

y =-x +10 is another 2nd equation with the same solution

there are an infinite number of 2nd linear equations that have the same (1,9) solution

also another infinite number of non-linear equations