Simplifying expressions
2a x 3b x 5
30ab
7(3 - x)
= 21 - 7x
2x + 5 = 9
x = 2
x2 = 121
x = 11 and - 11
Who teaches the other Year 9 5.3 class?
Mr Jordan
10t2 / 6t
5t / 3
-5(x - 3)
= -5x + 15
2a + 1/2 = 1/4
a = - 1/8
0.1 x2 = 1.6
x2 = 16
x = 4 and - 4
What happens in a leap year? (according to everyone other than Ayrton)
February has a 29th day.
xy + 8x + 4xy - 4x
5xy + 4x
1 - 5(x+4)
= 1 - 5x - 20
= - 5x - 19
5 + 3d/2 = -7
d = -8
5x2 - 32 = 43
Leave your answer in exact form.
5x2 = 75
x2 = 15
x = positive and negative square root of 15
What colour is Ms Nguyen's FitBit band?
pink
12m2n2 - 2mn2 - 4m2n2 + mn2
8m2n2 - mn2
2(4x - 3) - 2(3x - 1)
= 8x - 6 - 6x + 2
= 2x - 4
5m - 4 = 1 - 6m
11 m = 5
m = 5/11
This equation
x2 + 14 = 0
has no solution. Why not?
x2 = - 14
Taking a square root of a negative number gives no real solution, because no real number multiplied by itself would give a negative number.
What do the letters in SOLVE stand for?
Study, Organise, Line, Verify, Evaluate
The mean (average) mark on a test for 20 students is x. Another student who scores 75 is added to the list.
Write an expression for the new mean.
(x+75) / 21
Find an expanded expression for its area.
A = x(x + 4)
= x2 + 4x
- 4(x + 2) = 3(2x + 1)
- 4x - 8 = 6x + 3
- 10x = 11
x = - 11/10
Some practical situations involving measurement can be represented by quadratic equations. You would solve them normally by taking the square root. However, these quadratic equations would only have one solution. Explain why.
Many measurements e.g. length of a rectangle, radius of a circle, cannot be negative.
At recess today, Miss checked her phone. Her most recent notification was from which app?
Hint: It's boring lol
The FuelCheck app, saying the fuel price at her local station had just decreased.