maths 🧮 Flashcards
(25 cards)
What do you check in a ‘True or False’ equation?
Check if both sides are equal after simplifying.
Is this equation true? → 4(3) + 1 = 12 + 1
Yes! Both sides equal 13 ✅
Turn into an equation: ‘Double a number, subtract from 19 = 7’
19 − 2n = 7
Turn into an equation: ‘h plus 20 equals 164’
h + 20 = 164
Katya is k. Her sister is half her age and 6 years younger. Write the equation.
k/2 = k − 6
Solve: a + 5 = 18
a = 13
Solve: 6b = −42
b = −7
Solve: (c + 7)/3 = 9
Multiply by 3 → c + 7 = 27 → c = 20
Expand: 3(2d − 9) + 5d = 105
6d − 27 + 5d = 105 → 11d = 132 → d = 12
Solve: 6x + 5 = 4x + 17
Move terms → 2x = 12 → x = 6
Solve: 2(3e − 7) = 5(6 − e)
Expand both → 6e − 14 = 30 − 5e → e = 4
What is a term in algebra?
A part of an expression (e.g. 4x, −2y)
What is a coefficient?
The number in front of a letter (e.g. 5 in 5a)
What is a constant?
A number with no letter (e.g. 7 in 3x + 7)
Simplify: 3x + 4x
7x
Factorise: 6x + 12
6(x + 2)
What does ‘substitution’ mean?
Replace the letter with a number.
Index Law: x² × x³ = ?
x⁵ (add powers)
Index Law: y⁷ ÷ y² = ?
y⁵ (subtract powers)
Index Law: (z²)³ = ?
z⁶ (multiply powers)
Solve: 2x² = 50
x² = 25 → x = ±5
How many solutions? x² = 9
2 solutions (x = ±3)
How many solutions? x² = 0
1 solution (x = 0)
How many solutions? x² = −4
No real solution ❌
