Respuesta :

In the first equation, subtracting 14 from both sides gives

-a = 1

and then multipying both sides by -1 gives

a = -1

Question 2

Expanding the Left-hand side gives

21 - 7b = -42

Subtracting 21 from both sides gives

-7b = -63

dividing both sides by -7 gives

b = 9.