How do you solve the system of equations 3x + 5y - 30 = 03x+5y30=0 and x - y - 2 = 0xy2=0?

1 Answer
Sep 23, 2015

x = 5x=5
y=3y=3

Explanation:

3x+5y−30=03x+5y30=0---------------(1)
x−y−2=0xy2=0 -------------------(2)

Solve the equation (2) for yy

-y = 2-xy=2x
y = -2+xy=2+x

Substitute the value of y = -2+xy=2+x in equation (1)
3x+5( -2+x)−30=03x+5(2+x)30=0

Simplify

3x -10+5x −30=03x10+5x30=0
8x −40=08x40=0
8x =408x=40
x=40/8=5x=408=5
x = 5x=5

Substitute x = 5x=5 in equation (2)

5−y−2=05y2=0

Simplify -
3-y=03y=0
-y =-3y=3
y=3y=3

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