In linear algebra, the rank of a matrix
A
A is the dimension of the vector space generated (or spanned) by its columns.[1] This corresponds to the maximal number of linearly independent columns of
A
A. This, in turn, is identical to the dimension of the vector space spanned by its rows.[2] Rank is thus a measure of the "nondegenerateness" of the system of linear equations and linear transformation encoded by
A
A. There are multiple equivalent definitions of rank. A matrix's rank is one of its most fundamental characteristics.
The rank is commonly denoted by
rank
(
A
)
{\displaystyle \operatorname {rank} (A)} or
rk
(
A
)
{\displaystyle \operatorname {rk} (A)}; sometimes the parentheses are not written, as in
rank
A
{\displaystyle \operatorname {rank} A}.
In mathematics, an inverse function (or anti-function) is a function that "reverses" another function: if the function f applied to an input x gives a result of y, then applying its inverse function g to y gives the result x, and vice versa, i.e., f(x) = y if and only if g(y) = x. <u><em>Courtesy to Wikipedia</em></u>
Answer:
Step-by-step explanation:
Take one polynomial from the other means to perform the sub.traction of them. Recall that it is better to use grouping symbols when subtracting polynomials, so we get the signs right when combining like terms:
The indicated subtraction is: 
Make sure that before removing the grouping symbol (parenthesis) that is preceded by a negative sign, we change the signs of every term inside it. Then combine like terms to get the final answer:
Which is the last option shown in the question
Remark
There's a lot you don't know here. Are DE and GF parallel? Is B a right angle? You can't assume that it is. The safest way to proceed is to give x in terms of 58 and B. You might get an answer that gives you something like 32 but I don't think you can say that unless you are told somewhere that ABC is a right angle triangle with the right angle at B.
So what to do.
<BAC = 58o That's because <BAC = <IAK They vertically opposite.
<ABC + <BAC + <ACB = 180o All triangles have 180o
<ACB = 180 - 58 - <ABC Solve for an unknown angle of a triangle.
<ACB = 122 - <ABC
x = <ACB Vertically opposite angles.
x = 122 - <ABC Answer It's 32 if ABC is a right angle.
