Mental Maths Flashcards
1
Q
Basic algebra:
3x=9
A
x=3
2
Q
Basic algebra:
3x+6=12
A
x=2
3
Q
Basic algebra:
3x-6=12
A
x=6
4
Q
Basic algebra:
2x/6=6
A
x=18
5
Q
Simultaneous equations:
2x+y=10
y=x+1
A
x=3
y=4
6
Q
Simultaneous equations:
2x+y=15
x-y=6
A
x=7
y=1
7
Q
Simultaneous equations:
50x+10y=100
x+y=-6
A
Tip:
50x+10y=100 is the same as 5x+y=10. Just divide by 10.
x=4
y=-10
8
Q
Basic algebra:
x²=16
A
x=4
9
Q
Simultaneous equations:
2x+y=10
2x-y=6
A
x=4
y=2
10
Q
Expanding:
6(3x – 2y + z)
A
18x-12y+6z
11
Q
Expanding:
15(x²+4x+4)
A
15x²+60x+60
12
Q
Factorising:
15x²+60x+60
A
Tip:
15x²+60x+60 can be divided by 15 to get x²+4x+4 and then from there you get (x+2)(x+2)
