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Help, Solve it by using Elmination, Linear Equation

Help, Solve it by using Elmination, Linear Equation-example-1
User Walid
by
7.2k points

1 Answer

4 votes

Answer:

The mistake they made was that they subtracted
2y from
2y and got
0y. Instead of subtracting, they should have added it.

Explanation:

Given:


8x+2y=44\\5x+2y=35

We can combine the system of equations into a single equation:


13x+4y=79

From this step, we can conclude that the answer for part b is incorrect. The mistake they made was that they subtracted
2y from
2y and got 0y. Instead of subtracting, they should have added it.

We can continue solving the system of equations by writing y in terms of x.


8x+2y=44\\2y=44-8x\\y=22-4x

now substitute this into the single equation:


13x+4y=79\\13x+4(22-4x)=79\\13x+88-16x=79\\-3x+88=79\\-3x=-9\\x=3

Since we now know that
x=3\\, we can substitute this into the equation we made for y.


y=22-4x\\y=22-4(3)\\y=22-12\\y=10

The solution for the system of equations is
x=3 and
y=10\\.

User Onur Uslu
by
7.7k points