3(2a+5)+4(3a+1)=109

Solution for 3(2a+5)+4(3a+1)=109 equation:

Simplifying
3(2a + 5) + 4(3a + 1) = 109

Reorder the terms:
3(5 + 2a) + 4(3a + 1) = 109
(5 * 3 + 2a * 3) + 4(3a + 1) = 109
(15 + 6a) + 4(3a + 1) = 109

Reorder the terms:
15 + 6a + 4(1 + 3a) = 109
15 + 6a + (1 * 4 + 3a * 4) = 109
15 + 6a + (4 + 12a) = 109

Reorder the terms:
15 + 4 + 6a + 12a = 109

Combine like terms: 15 + 4 = 19
19 + 6a + 12a = 109

Combine like terms: 6a + 12a = 18a
19 + 18a = 109

Solving
19 + 18a = 109

Solving for variable 'a'.

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

Add '-19' to each side of the equation.
19 + -19 + 18a = 109 + -19

Combine like terms: 19 + -19 = 0
0 + 18a = 109 + -19
18a = 109 + -19

Combine like terms: 109 + -19 = 90
18a = 90

Divide each side by '18'.
a = 5

Simplifying
a = 5