2x + 7b is an expression. Since it is not an equation it cannot be solved. Furthermore, as an expression, there is no meaninful simplification, either.
If you mean: -3*(-2b-3)+7b then it is an algebraic expression that can be simplified to 6b+9+7b = 13b+9
4b - 3
-7a-7b
If you mean: 6(-3b-1)+2(7b-1) then it is -4b-8 simplified
2x + 7b is an expression. Since it is not an equation it cannot be solved. Furthermore, as an expression, there is no meaninful simplification, either.
It is: 7b+4b-1b = 10b when simplified
If you mean: -3*(-2b-3)+7b then it is an algebraic expression that can be simplified to 6b+9+7b = 13b+9
100a2 - 49b2 is the difference of two perfect squares. Therefore, it is equal to the sum times the difference of the roots: (10a + 7b)(10a - 7b)
If you mean 7b-2 = -51 then the value of b is -7
4b - 3
-7a-7b
If you mean: 6(-3b-1)+2(7b-1) then it is -4b-8 simplified
The given expression can be simplified to: 3b-a
b2 - 7b - 6b = -4(-4)2 - 7(-4) - 6 = 16 +28 - 6 = 38
2a+2a-7b+7b =4a
a + 7b + 2c