7.Solve forh:A= 2rh+ 2r.
8.Makethe subject of the formula:t=
D
f
.
9.Solve form:E=mgh+^12 mv^2.
10.Solve forx:x^2 +x(a+b) +ab= 0.
11.Solve forb:c=
p
a^2 +b^2.
12.MakeUthe subject of the formula:
1
V
=
1
U
+
1
W
.
13.Solve forr:A=R^2 r^2.
14.F=^95 C+32°is the formula for converting temperature in degrees Celsius to degrees Fahrenheit. Derive
a formula for converting degrees Fahrenheit to degrees Celcius.
15.V=^43 r^3 is the formula for determining the volume of a soccer ball. Express the radius in terms of the
volume.
16.Solve forxin:x^2 ax 3 x= 4 +a
17.Solve forxin:ax^2 4 a+bx^2 4 b= 0
18.Solve forxinv^2 =u^2 + 2axifv= 2,u=0,3,a=0,5
19.Solve foruinf′=f
v
v u
ifv= 13,f= 40,f′= 50
20.Solve forhinI=
bh^2
12
ifb= 18,I= 384
21.Solve forr 2 in
1
R
=
1
r 1
+
1
r 2
ifR=^32 ,r 1 = 2
For more exercises, visit http://www.everythingmaths.co.za and click on ’Practise Maths’.
1.2FFR 2.2FFS 3.2FFT 4.2FFV 5.2FFW 6.2FFX 7.2FFY 8.2FFZ
9.2FG2 10.2FG3 11.2FG4 12.2FG5 13.2FG6 14.2FG7 15.2FG8 16.2FG9
17.2FGB 18.2FGC 19.2FGD 20.2FGF 21.2FGG
http://www.everythingmaths.co.za m.everythingmaths.co.za
4.7 Solving linear inequalities EMA3H
A linear inequality is similar to a linear equation in that the largest exponent of a variable is 1. The following
are examples of linear inequalities.
2 x+ 2 1
2 x
3 x+ 1
2
4
3
x 6 < 7 x+ 2
The methods used to solve linear inequalities are similar to those used to solve linear equations. The only
difference occurs when there is a multiplication or a division that involves a minus sign. For example, we
know that 8 > 6. If both sides of the inequality are divided by 2, then we get 4 >