You can use the fact that only the like terms of the polynomial get added or subtracted by adding or subtracting their coefficients.
The reduced form of the given polynomials' subtraction is given by
Option B: [tex]11y - 10 + 2y^2[/tex]
Those terms which have same variables raised with same powers.
For example,
[tex]6x^2[/tex] and [tex]5x^2[/tex] are like terms since variable is same, and it is raised to same power 2.
For example
[tex]4x^3[/tex] and [tex]5x[/tex] are not like terms as the variables are same but powers aren't same.
Constants who are in multiplication with variables are called coefficients of those variables.
For example, in
[tex]10x^2[/tex]
we have 10 as coefficient of [tex]x^2[/tex]
Suppose we have [tex]5x^2 + 6y[/tex] . Since those terms are not like terms, their coefficient won't be add and the expression we've got right now, is its simplest form and cannot be reduced more.
If we have, suppose, [tex]4x + 5x^2 + 2x[/tex], then we see that 4x and 2x are like terms, their coefficient can be added and thus, the simplified form would be [tex](4+2)x + 5x^2 = 6x + 5x^2[/tex]
The given polynomials to be subtracted are
[tex]7y +2y^2 - 7\: \rm by\: 3 - 4y[/tex]
The subtraction will be done as:
[tex]\begin{aligned}7y + 2y^2 - 7 - (3-4y) &= 7y + 2y^2 - 7 - 3 + 4y \\&= (7+4)y + 2y^2 -7-3 \\&= 11y + 2y^2 - 10\\\end{algned}[/tex]
Thus, the reduced form of the given polynomials' subtraction is given by
Option B: [tex]11y - 10 + 2y^2[/tex]
Learn more about polynomial subtraction here:
https://brainly.com/question/9351663