ABSTRACT
In Problems 14 and 15, solve the simultaneous equations.
14. (a) 2x + y = 6 (b) 4x − 3y = 11 5x − y = 22 3x + 5y = 30 (9)
15. (a) 3a − 8+ b 8
= 0
b+ a 2
= 21 4
(b) 2p+ 1 5
− 1− 4q 2
= 5 2
1− 3p 7
+ 2q − 3 5
+ 32 35
= 0 (18) 16. In an engineering process two variables x and y
are related by the equation y = ax + b x , where a
and b are constants. Evaluate a and b if y = 15 when x = 1 and y = 13 when x = 3 (5)
17. Kirchhoff’s laws are used to determine the current equations in an electrical network and result in the following:
i1 + 8 i2 + 3 i3 = −31 3 i1 − 2 i2 + i3 = −5 2 i1 − 3 i2 + 2 i3 = 6
Determine the values of i1, i2 and i3 (10) 18. The forces acting on a beam are given by:
R1 +R2 = 3.3kN and 22× 2.7+ 61× 0.4− 12R1 = 46R2 Calculate the reaction forces R1 and R2 (8)
For lecturers/instructors/teachers, fully worked solutions to each of the problems in Revision Test 5, together with a full marking scheme, are available at the website:
