12*0.3+x*0.7=10

Solution for 12*0.3+x*0.7=10 equation:

Simplifying
12 * 0.3 + x * 0.7 = 10

Multiply 12 * 0.3
3.6 + x * 0.7 = 10

Reorder the terms for easier multiplication:
3.6 + 0.7x = 10

Solving
3.6 + 0.7x = 10

Solving for variable 'x'.

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

Add '-3.6' to each side of the equation.
3.6 + -3.6 + 0.7x = 10 + -3.6

Combine like terms: 3.6 + -3.6 = 0.0
0.0 + 0.7x = 10 + -3.6
0.7x = 10 + -3.6

Combine like terms: 10 + -3.6 = 6.4
0.7x = 6.4

Divide each side by '0.7'.
x = 9.142857143

Simplifying
x = 9.142857143