STEP 1: Recall what a solution is

https://virtualnerd.com/middle-math/equations-functions/expressions/equation-solution-definition

A solution is what which satisfies an equation.

STEP 2: Plug in the values as x = -9 and y = 8 in the equation 14x +18 y = 18

14(-9) + 18 (8) = -126 + 144 = 18

Since the left hand side of the equation is equal to the right hand side of the equation, we can say that (-9,8) is a solution to the equation 14 x + 18 y = 18

Next plug in x = -9 and y = 8 in the equation 13x +14 y = -5

we get 13(-9) + 14 (8) = -117 + 112 = -5.

Since the left hand side of the equation is equal to the right hand side of the equation, we can say that (-9,8) is a solution to the equation 13 x + 14 y = -5

So, (-9,8) is a solution to the system of equations