How do you solve the system of equations by graphing and then classify the system as consistent or inconsistent 3x-y=93xy=9 and 2x+y=62x+y=6?

1 Answer
Jan 8, 2018

(3,0)(3,0)

Explanation:

Given -

3x-y=93xy=9 -------------(1)
2x+y=62x+y=6 -------------(2)

If the slopes are different, both are consistent, else inconsistent.

When the equations are in the form

ax+by =cax+by=c
The formula for slope is m=- a/bm=ab
Slope of the first line m_1=- 3/(-1)=3m1=31=3
Slope of the second line m_2=- 2/1=2m2=21=2

The slopes are different. They are consistent.

We have to find the intercepts for the two lines to graph them

y-intercept of the 1st line

3(0)-y=93(0)y=9
y=-9y=9
(0, -9)(0,9)

x-intercept of the 1st line

3x-(0)=93x(0)=9
x=9/3=3x=93=3
(3,0)(3,0)

y-intercept of the 2nd line

2(0)+y=62(0)+y=6
y=6y=6
(0,6)(0,6)

x-intercept of the 2nd line

2x+0=62x+0=6
x=6/2=3x=62=3
(3, 0)(3,0)

[(3, 0)(3,0) is a common point for both the lines. Hence it is the solution]

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