What is the square root of 6.25?

See below

Step-by-step explanation:

Part A: The expression would be (4x+5)(3x+10), or, when expanded, 12x^2+55x+50 since the area of a rectangle is length*width

Part B: The degree is 2 because it's classified as a quadratic and trinomial expression

Part C: The closure property of polynomials is that polynomials will be closed under an operation if the operation produces another polynomial. For example, since we had to multiply two binomials in Part A, the exponents of x get combined to make x^2 (because x^1*x^1=x^(1+1)=x^2)