I don't understand how to do these problems, anyone that can help id appreciate it thank you.
Solve each system by substitutions solving for x then for y
x=5 3x+y=2
x+y= 8 4x+y=20
um why are there two equal signs in each equation? did you copy the problem correctly?
it was copied directly from my textbook x=5
x+y=8
that's my first problem
then I have
3x+y=2
4x+y=20
this is the second problem. and I need to solve for x and y but im confused an my examples aren't good from my notes. any help would be great.
To solve this system of equations by substitution, you need to solve one of the equations for either x or y, and then substitute that expression into the other equation. Let's start with the first system of equations:
First, we have x = 5 and x + y = 8. Since we already have x isolated in the first equation, we can substitute this value of x into the second equation:
5 + y = 8
Now, we can solve for y by subtracting 5 from both sides of the equation:
y = 8 - 5 = 3
So, we have found the value of y, which is 3. Now, we can substitute this value of y back into either of the original equations to find the value of x. Let's use the first equation:
x = 5
Therefore, x = 5.
So, the solution to the first system of equations is x = 5 and y = 3.
Now, let's move on to the second system of equations:
We have x = 5 and 3x + y = 2. To solve for y, we will substitute the value of x into the second equation:
3(5) + y = 2
Simplify the equation:
15 + y = 2
Now, subtract 15 from both sides of the equation:
y = 2 - 15 = -13
So, we have found the value of y, which is -13. Now, we can substitute this value of y back into either of the original equations to find the value of x. Let's use the first equation:
x = 5
Therefore, x = 5.
So, the solution to the second system of equations is x = 5 and y = -13.