Saturday
April 19, 2014

Homework Help: Equation of a straight line.

Posted by DJ Frankie Pigeon on Monday, January 15, 2007 at 3:09pm.

1. Find the equation of the line described in each case:

a) Gradient 3, cuts through (0, 6).

b) Steepness of 4, passes through (0, -2).

c)Parallel to y = 5x - 1, cuts the y-axis at (0, 10).

d)Cuts through (0, 7) and (5, 17)


2. Here are 3 eqautions:
A. y + 1 = 3x
B. y = -3(x - 1)
C. 2y = 8x + 6

Find the odd one out in each case:
a) Gradient is 3
b) Slopes in a positive direction
c) Cuts the y-axis at (0, 3)

3. A line passes through the point (10, 10). It's equation is y = mx + 4. Find the value of m.




I'll try to get you started on these, and let you take it from there.

For 1a:
y - y1 = m(x - x1)
y - 6 = 3(x - 0)
y - 6 = 3x
y = 3x + 6

For 1b:
Use the same procedure as 1a.

For 1c:
Parallel lines have the same slope.
y - 10 = 5(x - 0)
I'll let you finish.

For 1d:
m = (y2 - y1)/(x2 - x1)
m = (17 - 7)/(5 - 0)
m = 10/5 = 2
Therefore, using the first ordered pair (0, 7), we have this:
(y - 7)/(x - 0) = 2
y - 7 = 2(x - 0)
I'll let you take it from here to finish.

For 2a:
The coefficient of x is the slope.

For 2b:
Look for positive slopes.

For 2c:
Substitute 0 for x and 3 for y in each equation to check each one.

For 3:
Substitute 10 for x and 10 for y. Solve the equation for m, which is the slope.

I hope this will help get you started on these problems.

<<3. A line passes through the point (10, 10). It's equation is y = mx + 4. Find the value of m>>
Since y = mx + 4 and y = 10 when x = 10, plug those values of x and y into the eqwuation and solve for m.

Make an attempt at the others and we will glad to critique your work. Please limit your questions to one per post.

Answer this Question

First Name:
School Subject:
Answer:

Related Questions

Math - This question concerns the straight line that passes through the points...
Mathamatics - This question concerns the straight line that passes through the ...
mat 101 - Equation for a line that passes through (6,26) and has a slope of 3 ...
maths - Find the gradient of the straight line that passes through the points (3...
Math 101 - Find the equation for each of the following items below: a. A line ...
Math- finding equation - Can someone explain to me how to find the equation pf ...
algebra - Write an equation in slope-intercept form for each described line. 1....
math - the straight L has gradient 3 and passes through the point A(-6,4). a) ...
Straight Lines - The axes being inclined at an angle of 30, find the equation ...
Algebra - Write an equation in slope-intercept form for each described line. 1....

Search
Members