what is the solution (a, b) to this system of linear equations? 3a + 6b = 45 2a - 2b = -12 (-27, 6) (-1, 7)…

what is the solution (a, b) to this system of linear equations? 3a + 6b = 45 2a - 2b = -12 (-27, 6) (-1, 7) (1, 7) (27, -6)

what is the solution (a, b) to this system of linear equations? 3a + 6b = 45 2a - 2b = -12 (-27, 6) (-1, 7) (1, 7) (27, -6)

Answer

Explanation:

Step1: Multiply second - equation

Multiply the equation (2a - 2b=-12) by 3 to make the coefficient of (b) opposite of that in the first equation. (3\times(2a - 2b)=3\times(-12)), which gives (6a-6b = - 36).

Step2: Add the two equations

Add (3a + 6b=45) and (6a-6b=-36) together. ((3a + 6b)+(6a-6b)=45+( - 36)) (3a+6a+6b - 6b=45 - 36) (9a=9) (a = 1)

Step3: Substitute (a) into an equation

Substitute (a = 1) into the equation (2a-2b=-12). (2\times1-2b=-12) (2-2b=-12) (-2b=-12 - 2) (-2b=-14) (b = 7)

Answer:

C. ((1,7))