Question

Which ordered pair is the solution to the system of equations below when

using the matrix tool?
9x - 3y = 54
9x +1 ly = 12

Answer 1

(7, -3)

Explanation:

9x - 3y = 54

9x +1 ly = 12

Subtract both expresion

-3y - 11y = 54 - 12

-14y = 42

y = 42/-14

y = -3

Substitute y = -3 into 1;

From 1, 9x - 3y = 54

9x - 3(-3) = 54

9x - 9 = 54

9x = 54 + 9

9x = 63

x = 63/9

x = 7

Hence the solution to the system of equation is (7, -3)