SOLUTION: y=-5/3x-1 y=x+7 Its asking to solve equation by graphing, then it ask for X=? Y=?

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Question 1187243: y=-5/3x-1
y=x+7
Its asking to solve equation by graphing, then it ask for
X=?
Y=?

Found 3 solutions by Alan3354, josgarithmetic, Theo:
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
y=-5/3x-1
y=x+7
------------
Use parentheses.
y= (-5/3)x-1
y=x+7
-----
Graph the 2 lines.
The intersection is x & y

Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
The two lines intersect at some point (x,y) which you can find, through graphing if you want or are told to.

y=5x%2F3-1
vertical axis intercept is -1.
slope is 5%2F3.
Those read directly from the equation.

y=x%2B7
vertical axis intercept is 7.
slope is 1.
Those read directly from the equation.

Now you can easily graph the two lines on the same coordinate system and identify the intersection point.

Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
here's the graph.




the intersection point is at (x,y) = (12,19).

that means y = 19 when x = 12.

if you solve algebraically, you should get the same answer.

algebraically, you would do the following:

the two equatons that need to be solved simultaneously are:

y=-5/3x-1
y=x+7

since they are both equal to y, then 5/3 * x - 1 must be equal to x + 7.

you get:

5/3 * x - 1 = x + 7

subtract x from both sides of the equation and add 1 to both sides of the equation t0 get:

5/3 * x - x = 7 + 1

multiply both sides of this equation by 3 to get:

5 * x - 3 * x = 3 * (7 + 1)

combine like terms and simplify to get:

2*x = 24.

solve for x to get:

x = 24/2 = 12.

replace x in both original equations to get:

y=-5/3x-1 becomes y = 5/3 * 12 - 1 = 20 - 1 = 19.
y=x+7 becomes y = 12 + 7 = 19.

the value of x is 12 in both equations and the value of y = 19 in both equations.

both equations have been solved simultaneously by the value of x = 12 and y = 19.

the graphical solution provided the same answer.

that's because x = 12 when y = 19 is common to both equations which means it's also common to both lines on the graph created by those equations.