Page 145 - Mathematics

Example 6.15

y
A straight line is given by an equation 4x + + 6 0.= Find:
(a) Gradient
(b) x and y-intercepts Tanzania Institute of Education

Solution

y
Given 4x + + 6 0.= Express the equation in the form y = mx + . c That is,
y = − 4x − 6. Thus,
(a) gradient = −
4

6
(b) c = − and therefore y-intercept is (0, 6− ).

From y = − 4x − 6, substitute y = 0. It follows that,

0 = − 4x − 6,

4x = − 6
− 3
x =
2


Therefore, x-intercept is − 3 ,0 .


 2 

Example 6.16

Find the x and y-intercepts of the straight line 3x − 2y + 10 0.=

Solution
Given 3x − 2y + 10 0.= When x = 0, it implies that 2y = 10. Thus, y = 5.

Therefore, the y-intercept is (0, 5).

The x-intercept is obtained when y = 0. It implies that 3x = − 10, thus,
10
x = − .
3 Mathematics Form One
 10 
Therefore, x-intercept is − ,0 .


 3 

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25/10/2024 09:51:54
Mathematics form 1.indd 139 25/10/2024 09:51:54
Mathematics form 1.indd 139