Question

Two equations are given below:

a − 3b = 16
a = b − 2

What is the solution to the set of equations in the form (a, b)?

(−2, −6)

(−7, −9)

(−11, −9)

(−12, −10)

Answer 1

third one

Explanation:

Answer 2

`\left \{ {{a - 3b = 16} \atop {a = b - 2}} \right. \\ \\ \left \{ {{a = 16 + 3b} \atop { 16 + 3b = b - 2}} \right. \\ \\ \left \{ {{a = 16 + 3b} \atop {3b - b = - 2 - 16}} \right. \\ \\ \left \{ {{a =16 + 3b} \atop {2b = -18}} \right. \\ \\ \left \{ {{a=16 + 3b} \atop {b=-9}} \right. \\ \\ \left \{ {{a=16 + 3b = 16 + 3*(-9) = 16 - 27 = -11} \atop {b=-9}} \right.`

Answer a = -11, b = -9