SOLUTION: Which of the following equations will produce a graph with the intersection of two lines at the positive 2 on the x axis? A. 3x - 2y =6 2x+y=4 B. -3x-2y=6

Algebra.Com
Question 674276: Which of the following equations will produce a graph with the intersection of two lines at the positive 2 on the x axis?


A. 3x - 2y =6
2x+y=4
B. -3x-2y=6
-2x+y=4
C. 3x + 2y=6
2x-y= 4
D. 3x - 2y =-6
2x+y = -4


Found 2 solutions by ewatrrr, fcabanski:
Answer by ewatrrr(24785)   (Show Source): You can put this solution on YOUR website!
 
Hi
two lines intersecting at the positive 2 on the x axis.
That would mean the two lines both have x-intercepts = 2
That is... when y = 0 ⇒ x = 2
A.
3x - 2y =6 || y = 0 ⇒ x = 2
2x + y =4 || y = 0 ⇒ x = 2
C.
3x + 2y=6 || y = 0 ⇒ x = 2
2x - y= 4 || y = 0 ⇒ x = 2
Answer by fcabanski(1391)   (Show Source): You can put this solution on YOUR website!
One method is to set each equation in the form y=mx+b, set those two equations equal to each other, solve for x, and then plug x back into either equation to solve for y. For this problem you don't have to plug the x value back into one of the equations because the problem doesn't ask for the y value.


A. Equation 1: 3x - 2y =6 (subtract 3x from both sides) -2y =-3x +6 (divide both sides by -2) y = 3/2 x -3


Equation 2: 2x+y=4 (subtract 2x from both sides) y = -2x + 4.


Set the equations = to each other: 3/2 x - 3 = -2x + 4 (add 2x to both sides, add 3 to both sides) 7/2x = 7 (multiply both sides by 2/7) x = 2.


A is an answer because the x value of the intersection point is 2.


B: Equation 1: -3x-2y=6 ---> -2y = 3x + 6 ---> y = -3/2 x - 3


Eq 2: -2x+y=4 ---> y = 2x + 4


Set the equations = and solve for x. -3/2 x - 3 = 2x + 4 ---> 1/2 x = 7 ---> x = 14


B isn't an answer.


C: EQ 1 3x + 2y=6 ---> 2y = -3x + 6 ---> y = -3/2 x + 3


EQ 2 : 2x-y= 4 ---> -y = -2x + 4 ---> y = 2x - 4


Set them equal: -3/2 x + 3 = 2x - 4 ---> -7/2 x = - 7 ---> x = 2


C is an answer.


D: EQ1: 3x - 2y =-6 ---> -2y = -3x -6 ---> y = 3/2 x + 3


EQ2: 2x+y = -4 ---> y = -2x - 4


Set the equations = to each other: -2x - 4 = 3/2 x + 3 ---> -3x = 7 ----> x = -7/3 not an answer.

Hope the solution helped. Sometimes you need more than a solution. Contact fcabanski@hotmail.com for online, private tutoring, or personalized problem solving (quick for groups of problems.)

RELATED QUESTIONS

On a graph paper, draw the two straight lines which represent the equations 2x – y = 3... (answered by math-vortex)
The lines y = 2x + 4 and x + y = 13 make angles of a° and b° with the positive... (answered by Boreal)
10. Which of the following phrases correctly describes the graph of the system of... (answered by Alan3354)
My Algebra II teacher gave us a graph with two lines on it. The numbers are 8,000 to... (answered by scott8148)
The points (1, 3), (2, 5), (8, 17), (50, 101), and (1000, 2001) all lie on line M. The... (answered by checkley77)
The points(1,3),(2,5),(8,17),(50,101) and (1000, 2001) all lie on line M. The... (answered by stanbon)
I really really need your help. The points (1, 3), (2, 5), (8, 17), (50, 101), and... (answered by Fombitz)
Find the two coordinates of the intersection of the following two lines: x+2y=5 and... (answered by robertb)
How do we write the equation of a vertical line? what would be an example? The points... (answered by stanbon)