Question

Use the substitution method to solve the following system of linear equations:

2x + 2y = 10
x = –y + 5

Answer 1

A.
The solution is (4, –1).

B.
There are an infinite number of solutions.

C.
There is no solution.

D.
The solution is (2, –3).

Answer 2

x = -y + 5
now sub -y + 5 in for x in the other equation
2x + 2y = 10
2(-y + 5) + 2y = 10
-2y + 10 + 2y = 10
-2y + 2y = 10 - 10
0 = 0
INFINITE SOLUTIONS

That is using the substitution method, but if you look at the equations..
x = -y + 5
x + y = 5

2x + 2y = 10 -- divide by 2
x + y = 5

you will see that they are the same line and therefore have infinite solutions.

Answer 3

thanks

Answer 4

sure thing :)