WRSC General Maths

Solving simple equations

100

The cost of hiring a wedding reception is given by the rule: C= 80p + 1000

where C is the total cost in dollars and p is the number of people attending.

Find the cost of hiring when 120 people attend.

$10,600

200

Is x² + 3 = 9 a linear equation?

No- the power of x is 2, not 1.

300

Find the circumference of a circle when the radius is 25cm. Round off to the nearest decimal.

157.1cm

400

Solve the equation 4(x-3) = 24.

x = 9

500

If x + 5y = 9, find an expression for x.

x = 9-5y

Non-linear & transposing

100

Solve the equation x² = 49

x = +/- 7

200

Solve the equation a³ = -512.

a = -8

300

Transpose I = PRT/100 to make R the subject. 

R = 100I/PT

400

Transpose p = st + (1/4)ar² to make a the subject.

a = 4(p-st)/r²

500

Transpose v = 2t + 5 to make t the subject. Then find the value of t when v = 14.9

t = (v+s)/2 

t = 9.95

Simultaneous equations

100

Solve the following equations simultaneously:

y=x+3

6x+y=17

x= 2, y=5

200

Solve the following equations:

x+8y=16

y-x=2

x=0, y=2

300

Solve the following equations:

2x+3y=12

4x-3y=6

x=3, y=2

400

Solve the following equations:

4x-3y=6

5y-2x=4

x=3, y=2

500

Solve the following equations:

4x+3y= -28

-6y+5x= -35

x= -7, y=0