72=(a*10)+(a*2a)

Solution for 72=(a*10)+(a*2a) equation:

Simplifying
72 = (a * 10) + (a * 2a)

Reorder the terms for easier multiplication:
72 = (10a) + (a * 2a)

Reorder the terms for easier multiplication:
72 = (10a) + (2a * a)

Multiply a * a
72 = (10a) + (2a2)

Solving
72 = (10a) + (2a2)

Solving for variable 'a'.

Reorder the terms:
72 + (-10a) + (-2a2) = (10a) + (-10a) + (2a2) + (-2a2)

Combine like terms: (10a) + (-10a) = 0
72 + (-10a) + (-2a2) = 0 + (2a2) + (-2a2)
72 + (-10a) + (-2a2) = (2a2) + (-2a2)

Combine like terms: (2a2) + (-2a2) = 0
72 + (-10a) + (-2a2) = 0

Factor out the Greatest Common Factor (GCF), '2'.
2(36 + (-5a) + (-1a2)) = 0

Factor a trinomial.
2((4 + -1a)(9 + a)) = 0

Ignore the factor 2.
Subproblem 1
Set the factor '(4 + -1a)' equal to zero and attempt to solve:

Simplifying
4 + -1a = 0

Solving
4 + -1a = 0

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

Add '-4' to each side of the equation.
4 + -4 + -1a = 0 + -4

Combine like terms: 4 + -4 = 0
0 + -1a = 0 + -4
-1a = 0 + -4

Combine like terms: 0 + -4 = -4
-1a = -4

Divide each side by '-1'.
a = 4

Simplifying
a = 4
Subproblem 2
Set the factor '(9 + a)' equal to zero and attempt to solve:

Simplifying
9 + a = 0

Solving
9 + a = 0

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

Add '-9' to each side of the equation.
9 + -9 + a = 0 + -9

Combine like terms: 9 + -9 = 0
0 + a = 0 + -9
a = 0 + -9

Combine like terms: 0 + -9 = -9
a = -9

Simplifying
a = -9
Solution
a = {4, -9}