Answer:
C. 
Step-by-step explanation:
Given the two equations:
To find:
The correct option when value of y is substituted to 2nd equation using the 1st equation.
Solution:
First of all, let us learn about the substitution method.
Substitution method is the method to provide solutions to two variables when we have two equations and two variables.
In substitution method, we find the value of one variable in terms of the other variable and put this value in the other equation.
Now, the other equation becomes only single variable and then we solve for the variable's value.
Here, we have two equations and value of one varible is:
Let us put value of y in 2nd equation:
So, the correct answer is option C.
Answer:
3
Step-by-step explanation:
The average rate of change is
f(x2) - f(x1)
-----------------
x2-x1
We want to find the change from 1 to 3
f(3) = 8
f(1) = 2
f(3) - f(1) 8-2 6
----------------- = ------------ = ---- = 3
3-1 2 2
For systems of equations try using graphing, substitution, and elimination. For example
{2x+7y=3}
{x=-4y}
You should first look at if you have a variable that can be substituted (using substitution) and in this case we do! you plug in the x into 2x meaning 2(-4y)+7y=3
1) distribute -8y+7y=3
2) combine like terms in this case -8y+7y= -1y
3) solve -1y=3
y=-3
so currently our solution is (0,-3)
now we solve for x.
we plug our solved variable (y) into 7y
7(-3) and our equation looks like this
2x+7(-3)=3
1) distribute 7(-3)=-21
2) rewrite then solve 2x+(-21)=3
3) isolate variable -21+21 & 3+21
4) 2x=24
5) solve 2/24 = 12
Meaning our solution is (12,-3)
This is how to solve by substitution.
C. The system has no solution.
