Question

What is the x value of the solution to the following system
x + y =40
x - 3y = -4

Answer 1

C) 29

Explanation:

1st equation - 2nd equation,

x+y - (x-3y) = 40-(-4)

x+y-x+3y = 40+4

4y = 44

y = 44÷4

y = 11

substituting y into the first equation,

x + 11 = 40

x = 40-11 = 29

answer is C

hope it helps. :)

Answer 2

x=y , x-3y=4. x = y x = y , x − 3y = 4 x - 3 y = 4. Replace all occurrences of x x with y y in each equation. Tap for more steps... −2y = 4 - 2 y = 4. x = y x = y. Divide each term in −2y = 4 - 2 y = 4 by −2 - 2 and simplify. Tap for more steps... y = −2 y = - 2.

Explanation:

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