Solve the simultaneous equations: 6a + b = 16 and 5a - 2b = 19

Rearrange the first equation to give b as the subject.

b = 16 - 6a

Then substitute that equation for b into the second equation.

5a - 2(16 - 6a) = 19

Simplify this equation (remembering to take account of the double negative) and solve for a.

5a - 32 + 12a = 19

17a - 32 = 19

17a = 51

a = 3

Substitute the value of a into the previous equation for b and solve.

b = 16 - (6 x 3)

b = 16 - 18

b = -2