Step 3: Substitute values and solve fory6 ( 3)
2 2
y 3
7 4= 1
9
4
y 3
3= 1
y 3
3= 1
4
9
y 3
3=
4
9
y 3 =4
9
3
y 3 =4
3
y=4
3
+ 3
=
4 + 9
3
=
13
3
= 4
1
3
Step 4: Write the final answer
Therefore the coordinates ofDare(
7; 4^13
)
.
Horizontal and vertical lines EMA6F
A line that runs parallel to thex-axis is called a horizontal line and has a gradient of zero. This is because there
is no vertical change:
m=change iny
change inx=
0
change inx= 0
A line that runs parallel to they-axis is called a vertical line and its gradient is undefined. This is because there
is no horizontal change:
m=change iny
change inx=
change iny
0= undefinedPoints on a line EMA6G
A straight line is a set of points with a constant gradient between any of the two points. There are two methods
to prove that points lie on the same line: the gradient method and a method using the distance formula.
NOTE:
If two points lie on the same line then the two points are said to be collinear.302 8.3. Gradient of a line