3a(3a-7)+7(3a-7)=

Solution for 3a(3a-7)+7(3a-7)= equation:

Simplifying
3a(3a + -7) + 7(3a + -7) = 0

Reorder the terms:
3a(-7 + 3a) + 7(3a + -7) = 0
(-7 * 3a + 3a * 3a) + 7(3a + -7) = 0
(-21a + 9a2) + 7(3a + -7) = 0

Reorder the terms:
-21a + 9a2 + 7(-7 + 3a) = 0
-21a + 9a2 + (-7 * 7 + 3a * 7) = 0
-21a + 9a2 + (-49 + 21a) = 0

Reorder the terms:
-49 + -21a + 21a + 9a2 = 0

Combine like terms: -21a + 21a = 0
-49 + 0 + 9a2 = 0
-49 + 9a2 = 0

Solving
-49 + 9a2 = 0

Solving for variable 'a'.

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

Add '49' to each side of the equation.
-49 + 49 + 9a2 = 0 + 49

Combine like terms: -49 + 49 = 0
0 + 9a2 = 0 + 49
9a2 = 0 + 49

Combine like terms: 0 + 49 = 49
9a2 = 49

Divide each side by '9'.
a2 = 5.444444444

Simplifying
a2 = 5.444444444

Take the square root of each side:
a = {-2.333333333, 2.333333333}