What is the solution to the system of equations? {x+y=7x=y+3

Mathematics

1 answer:

abruzzese [7]3 years ago

7 0

<h3>Answer:</h3>

x=5, y=2

<h3>Explanation:</h3>

The second equation gives an expression for x that can be substituted into the first equation.

... (y+3) +y = 7 . . . . . .substitute y+3 for x

... 2y + 3 = 7 . . . . . . . colect terms

... 2y = 4 . . . . . . . . . . subtract 3 from both sides

... y = 2 . . . . . . . . . . . . divide both sides by 2

Using the expression for x, we can find its value.

... x = y + 3

... x = 2 + 3 . . . . . . . . . substitute for y

... x = 5

The solution is (x, y) = (5, 2).

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