Expanding
Expand:
3x(x-5)
2x+6
Factorise:
12x^2y+8xy^2
4xy(3x+2y)
A student is asked to expand, and they write:
2(x+3)=2x+3
What's the mistake, and what is the correct answer?
Didn't multiply the 3 by 2.
Answer:
2x+6
A square has side length x+3 . Write an expression for its area.
(x+3)^2=x^2+6x+9
What famous movie features a family of clownfish?
Finding Nemo!
Expand and simplify:
x(x+1)+2(x+1)
x^2+3x+2
Factorise:
y^2+7y-18
(y+9)(y-2)
A student is asked to expand, and they write:
-(x+3)-(2x-4)=-x-3-2x-4
What's the mistake, and what is the correct line?
Didn't flip the sign on the -4
Answer:
-x-3-2x+4
A rectangle has area x^2+7x+10 . Write factorised expressions for its length and width.
(x+5)(x+2)
In what country were the 2024 Summer Olympics held?
France (Paris)
Expand:
(3x+4y)(2x+5y)
6x^2+23xy+20y^2
Factorise:
3x^2-10x-8
(3x+2)(x-4)
A student is asked to expand, and they write:
(x+5)^2=x^2+25
What's the mistake, and what is the actual answer?
Forgot the 2ab middle term!
Answer:
x^2+10x+25
A triangle has base 2x+4 and height x+2 . Write a fully simplified expression for its area.
\frac{1}{2}(2x+4)(x+2)
=\frac{1}{2}(2x^2+8x+8)
=x^2+4x+4
What is the chemical symbol for Gold?
Au
Expand:
(3x-\frac{2}{5}y)^2
9x^2-\frac{12}{5}xy+\frac{4}{25}y^2
Factorise:
x^2-81
(x-9)(x+9)
A student is asked to factorise fully, and they write:
2x^2+8x+6=(2x+2)(x+3)
What's the mistake, and what is the actual answer?
Forgot to take out the common factor of 2!
Answer:
2(x+1)(x+3)
A square has side x+3 . A smaller square of side x+1 is cut from it. Write a simplified expression for the remaining area.
(x+3)^2-(x+1)^2=4x+8
In Minecraft, what materials do you need to craft a compass (and how many of each).
4 iron ingots and 1 redstone dust.
Expand:
(x+2)^2(x-1)
x^3+3x^2-4
(Double Points!!!)
Factorise:
6x^2+13xy-5y^2
(2x+5y)(3x-y)
A student is told a rectangle has a length 2x+3 and width x-1 and is asked to find the area.
The student writes:
(2x+3)(x-1)
=2x^2-2x+3x-3
=2x^2+x+3
Sign error on the last term should be -3 not +3.
Answer:
2x^2+x-3
A rectangle has area 2x^2+5x+3 and one side is 2x+3 . Write a factorised expression for the other side, then simplify the expression for the perimeter of the rectangle.
Rectangle =(2x+3)(x+1)
Perimeter 2(x+1)+2(2x+3)=6x+8
I am the only planet in our solar system that rotates on its side, I spin backwards compared to most other planets, and despite not being the closest planet to the Sun, my surface is hot enough to melt lead.
What planet am I?
Venus