Page 101 - Mathematics

1
Substitute b = into equation (ii) 17
3 7x −  4y =
to obtain the value of a. 5.  5x − 4y = 11

From a + 6b = 1. It implies that, 6.  0.7x −  0.5y = 2.5

1    0.7x + 0.3y = 2.9 Tanzania Institute of Education
a + 6   = 1. 0

3   7.  2x y+=
2
a += 1.  x − 2y = − 5
a = − 1  4 + 1 = 3

1 1 8.  x y
But, a = and b = . It follows  1 2
x y  + = − 1
1 1 1  x y

that, 1− = and = .
x 3 y  8 12 = − 2
−
Solving for the values of x and y 9.  x y

gives,  5 + 3 = 1

x = − 1 and y = 3.  x 2y

3
Therefore, x = − and y = is 0.2x +  0.3y = 0.1
1
the solution of the simultaneous 10.  0.3x − 0.1y = 0.7

equation.
0.05x +  0.02y = 0.01
Exercise 5.5 11.  0.02x − 0.03y = − 0.11


Solve the following simultaneous  1 x + 3y = 3


equations by using elimination 12.  2
method.  3 x − 2y = − 2
y
 2x += 5   4
1. 
 4x y−= 7 u + 2v = 1
13. 
 3pq+ = 6  3u − 4v = 8
2. 
 5pq+ = 8  2pq+ = 4
5x −  2y = 16 14.  − 3p + 5q = − 19

3. 
 x + 2y = 8  1 n = 3 Mathematics Form One
8x +  5y = 40 15.  2m +  3
4.   − 3mn+= 6
 9x − 5y = 5 

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25/10/2024 09:51:32
Mathematics form 1.indd 95 25/10/2024 09:51:32
Mathematics form 1.indd 95