Question

40=10-6a

Answer 1

40 = 10 + -6a

Move all terms containing a to the left, all other terms to the right.

Add '6a' to each side of the equation.
40 + 6a = 10 + -6a + 6a

Combine like terms: -6a + 6a = 0
40 + 6a = 10 + 0
40 + 6a = 10

Add '-40' to each side of the equation.
40 + -40 + 6a = 10 + -40

Combine like terms: 40 + -40 = 0
0 + 6a = 10 + -40
6a = 10 + -40

Combine like terms: 10 + -40 = -30
6a = -30

Divide each side by '6'.
a = -5

Simplifying
a = -5