Answer: This is what I could figure out
Step-by-step explanation:
On solving the linear system, for the value of y = 15, the value of x is 200. The correct option is D.
<h3>What is the linear system?</h3>
It is a system of an equation in which the highest power of the variable is always 1. A one-dimension figure that has no width. It is a combination of infinite points side by side.
Given
The linear equation is shown below.

The equation can be written as

For y = 15, the value of x will be.

The value of x is 200.
Thus, option D is correct.
More about the linear system link is given below.
brainly.com/question/20379472
Answer:
The fundamental theorem of algebra guarantees that a polynomial equation has the same number of complex roots as its degree.
Step-by-step explanation:
The fundamental theorem of algebra guarantees that a polynomial equation has the same number of complex roots as its degree.
We have to find the roots of this given equation.
If a quadratic equation is of the form 
Its roots are
and 
Here the given equation is
= 0
a = 2
b = -4
c = -1
If the roots are
, then
= 
= 
= 
= 
= 
= 
These are the two roots of the equation.
A=adult
c=children
total lumber=30
total number=adults+children
a+c=30
total cost=50
total cost=acost+ccost
acost=a times cost per adult=a times 3=3a
ccost=c times cost per child=c tiems 1=1c=c
total cost=3a+c
50=3a+c
equiaotn are
a+c=30
3a+c=50
multiplyu first by -1 and add
3a-a+c-c=50-30
2a=20
a=10
sub
10+c=30
c=20
answer is A