Find the slope of line L which passes through the point (-1,2)

Question

Find the slope of line L which passes through the point (−1, 2) and the point of intersection of lines 2x + 3y = 5 and x + 2y = 3.

0
1
−1/2
1/3
1/2

gsingh0711 · Accepted Answer

xplanation:

Slope of line passing through points (x1, y1) and (x2, y2) is given by, m=y2−y1x2−x1

Given that line L passes through the point (−1, 2) and the point of intersection of lines 2x + 3y = 5 and x + 2y = 3
To find point of intersection, we solve the 2 equations
2x + 3y = 5
x + 2y = 3
Multiplying second equation by 2 and subtracting first equation, we get
y = 1 and x = 1
⇒ line 1 passes through (1, 1) and (−1, 2).

Using the slope formula:
m=2−1(−1)−1=−1/2
Answer: C.

I think, I deserve a kudus LOL :D

generis · Answer

gsingh0711  - what are the answer choices for this question?

ScottTargetTestPrep · Answer

To find the point of intersection of lines 2x + 3y = 5 and x + 2y = 3, we solve the equations simultaneously.

Multiplying the second equation by -2 and adding the result to the first equation, we have:

-y = -1

y = 1

Now substituting 1 for y in 2x + 3y = 5, we have:

2x + 3 = 5

2x = 2

x = 1

Therefore, the point of intersection of the two lines is (1, 1). Now we can find the slope between this point and (-1, 2) using the slope formula:

m = (2 - 1)/(-1 - 1) = 1/(-2) = -1/2

Answer: -1/2

SvelteNigerian · Answer

But when you solve the equations you get x+y=2 and when you write it in the slope intercept form, you get y = -x + 2; so how did you get the value of x to be 1 instead of -1. Please explain what im missing...thanks

MathRevolution · Answer

For slope, we need two points pair.

One is (−1, 2).

Other will be the point of intersection of lines 2x + 3y = 5 and x + 2y = 3.

Solving equations: 2x + 3y - 2x - 4y = 5 - 6

=> y = 1 and x = 1.

Slope:  \frac{1-2 }{ 1 - (-1)} = \frac{-1}{2}

Answer C

Find the slope of line L which passes through the point (-1,2)

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GMAT Problem Solving (PS) Questions

Find the slope of line L which passes through the point (-1,2)

Prep Toolkit

615 to 715 in 15 Days (Ria's Strategies)

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Perfect 805 Score Debrief by Julia

My Rewards