SOLUTION: Solve the system by addition. If a unique solution does not exist, state whether the system is inconsistent or dependent. 10x=2Y=7, Y=-5X+3 Show your solution below: W

Algebra ->  Graphs -> SOLUTION: Solve the system by addition. If a unique solution does not exist, state whether the system is inconsistent or dependent. 10x=2Y=7, Y=-5X+3 Show your solution below: W      Log On


   



Question 124714: Solve the system by addition. If a unique solution does not exist, state whether the system is inconsistent or dependent.
10x=2Y=7, Y=-5X+3
Show your solution below:

What is the solution for this system?
What type of system is this?

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

10x%2B2Y=7....
+Y=-5X%2B3+....in standard form will be:
+5X+%2B+Y=+3+....
Solved by pluggable solver: Solving a System of Linear Equations by Elimination/Addition


Lets start with the given system of linear equations

10%2Ax%2B2%2Ay=7
5%2Ax%2B1%2Ay=3

In order to solve for one variable, we must eliminate the other variable. So if we wanted to solve for y, we would have to eliminate x (or vice versa).

So lets eliminate x. In order to do that, we need to have both x coefficients that are equal but have opposite signs (for instance 2 and -2 are equal but have opposite signs). This way they will add to zero.

So to make the x coefficients equal but opposite, we need to multiply both x coefficients by some number to get them to an equal number. So if we wanted to get 10 and 5 to some equal number, we could try to get them to the LCM.

Since the LCM of 10 and 5 is 10, we need to multiply both sides of the top equation by 1 and multiply both sides of the bottom equation by -2 like this:

1%2A%2810%2Ax%2B2%2Ay%29=%287%29%2A1 Multiply the top equation (both sides) by 1
-2%2A%285%2Ax%2B1%2Ay%29=%283%29%2A-2 Multiply the bottom equation (both sides) by -2


So after multiplying we get this:
10%2Ax%2B2%2Ay=7
-10%2Ax-2%2Ay=-6

Notice how 10 and -10 and 7 and -2 add to zero (ie 10%2B-10=0 2%2B-2=0)

However 7 and -6 add to 1 (ie 7%2B-6=1);


So we're left with

0=1


which means no value of x or y value will satisfy the system of equations. So there are no solutions


So this system is inconsistent