118k views
1 vote
Find an equation of the line that passes through the point (-1, 7) and is parallel to the line passing through the points (-3, -4) and (1, 4). (Let x be the independent variable and y be the dependent variable.)

User Noella
by
7.8k points

2 Answers

6 votes

Final answer:

To find a line parallel to another, determine the slope of the original line, which is 2 in this case, and then use the point-slope form with a given point and the same slope to find the equation, resulting in y = 2x + 9.

Step-by-step explanation:

To find an equation of the line that is parallel to another, we must first determine the slope of the given line. The line passing through the points (-3, -4) and (1, 4) has a slope calculated by the formula ∆y/∆x = (4 - (-4))/(1 - (-3)) = 8/4 = 2.

Since parallel lines have the same slope, our new line will also have a slope of 2. We can use the point-slope form of a line's equation, which is y - y1 = m(x - x1), where m is the slope and (x1, y1) is a point on the line. Substituting our known point (-1, 7) and the slope 2, we get y - 7 = 2(x - (-1)). Simplified, the equation of our parallel line is y = 2x + 9.

User Freejosh
by
7.0k points
7 votes

Answer:
y=2x+9

Step-by-step explanation:

Slope of line passing through (a,b) and (c,d) =
m=(d-b)/(c-a)

⇒ Slope of line passing through (-3, -4) and (1, 4) =
m=(4-(-4))/(1-(-3))


(4+4)/(1+3)=(8)/(4)=2

i.e. Slope of line passing through (-3, -4) and (1, 4) = 2

We know that the slopes of two parallel lines are equal.

Therefore , the slope of line parallel to the line passing through the points (-3, -4) and (1, 4)= 2

Also, equation of line passing through point (a,b) and has slope m :


(y-b)=m(x-a)

Then, the equation of line passing through point (-1, 7) and has slope 2 :


(y-7)=2(x-(-1))\\\\y-7=2(x+1)\\\\ y-7=2x+2\\\\ y=2x+2+7=2x+9\\\\ y=2x+9

Hence, the required equation of the line that passes through the point (-1, 7) and is parallel to the line passing through the points (-3, -4) and (1, 4).


y=2x+9

User EchoAro
by
9.2k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories