SOLUTION: I am trying to graph the equation -6x+10y=-60 and 7x-6y=-42 on the cognitive tudor I can not find the correct intersections for x and y to complete the problem can you help me plea

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Question 305455: I am trying to graph the equation -6x+10y=-60 and 7x-6y=-42 on the cognitive tudor I can not find the correct intersections for x and y to complete the problem can you help me please!
Found 3 solutions by richwmiller, edjones, Theo:
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
What is a cognitive tudor?

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
-6x+10y=-60
10y=6x-60
y=.6x-10
.
7x-6y=-42
-6y=-7x-42
y=(7x/6)+7
.
Ed
.
graph%28500%2C500%2C-40%2C10%2C-40%2C10%2C.6x-10%2C%287x%2F6%29%2B7%29

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
To graph the equation -6x + 10y = -60, you have to solve for y to get:

y = (6x -60)/10

To graph the equation 7x - 6y = -42, you have to solve for y to get:

y = (7x + 42)/6

The graph looks like this:

graph%28600%2C600%2C-30%2C10%2C-30%2C10%2C%286x-60%29%2F10%2C%287x%2B42%29%2F6%29

The intersection of these lines looks like it is around (-23,-20).

To find the intersection, solve these equations simultaneously.

The equations are:

-6x + 10y = -60
7x - 6y = -42

Multiply the first equation by 7 and the second equation by 6 to get:

-42x + 70y = -420
42x - 36y = -252

Add these 2 equations together to get:

34y = -672

Divide both sides of this equation by 34 to get:

y = -19.76470588

Substitute for y in the first original equation to get:

-6x + 10y = -60 becomes:

-6x - 197.6470588 = -60

Add 197.6470588 to both sides of this equation to get:

-6x = 137.6470588

Divide both sides of this equation by -6 to get:

x = -22.94117647

You have an intersection at:

x = -22.94117647
y = -19.76470588

The graph confirms that in the detail it is possible to get from the graph.

The easiest way to estimate is to use a piece of paper and line up the horizontal side of the paper with the bottom of your computer screen and then see what the x-value is by sliding the paper sideways.

You can see what the y-value is by lining up the paper with the y-axis and then sliding the paper up and down until you can estimate what the y-value of the instersection is.