Power of Maths: Paper 1 – Section 3 EXERCISE 6 (A) CONCEPTS AND SKILLS
Solve the following pairs of linear simultaneous equations:
1. 2x + y = 7 2x − y = 1
2. 3x + y = 7 2x − y = 3
3. 2x + y = 8 5x − y = 6
4. 2x − 3y = −5 x + y = 5
5. x − 5y = 11 2x + y = 0
6. 2x + 3y = 5 3x + 4y = 7
7. 5x + 4y = 22 3x + 5y = 21
8. 5x + 3y = 29 4x + 7y = 37
9. 2x − 5y = 8 2x − 3y = −6
10. 3y − 4x = −10 y + 4x = 8
11. 2x − 5y = 3 x − 3y = 1
12. 3x − 5y = 44 5x + 7y = 12
13. 2x − 3y = 24 5x
___ 3 −
14. x __
__ 4 +
2 + x
__ 2 = 12
y
__ 5 = 4
y
__ 2 = 6
y
15. 4x + 11 = 3y 3(x − 2) − 7y = 0
120
16. 7 − 6 (x − 3y) = 4 3 (x + 2y) + 6 = 5x + 10y
17.
_______ 4 −
3(x + 2)
______ 2
(y + 3)
__________ 6
5(x − y + 2)
= 5 __
2
18. If y = a + bx, fi nd a and b, given y = 7 when x = –2 and y = 10 when x = 4.
19. The straight-line graph of y = a + bx is shown. Find a and b.
y
4 6 8
2 0 1 2 x
20. The volume of oil in a tank is decreasing linearly with time. Find the equation of the straight line V = a + bt by fi nding a and b. Find V when t = 0.
V
2 3
1 0 1 2 3 4 5 Time (hours)
(B) CONTEXTS AND APPLICATIONS Numbers
1. The sum of two numbers is 135. Their difference is 7. Find them.
2. The difference of two numbers is 3. If three times the larger number less twice the smaller one is 13, fi nd them.
