Substitution 1
When a=2
a + 4
= 6
When x=3 and y=10
xy
= 30
a + a + a
b + c + c + c
= b + 3c
When w=7
w + w + w + w + w
= 35
When c=4
3c
= 12
When k=3, m=12 and n=20
k + m + n
= 35
a x a x a
= a^3
10s - 2w + 5s
= 15s - 2w
When v=11
4v
= 44
When b=5
20 - b
= 15
When b=12 and c=6
b + c - 3
= 15
2gh + 2ef - 2gh + 2ef
= 4ef
11rt - 3rt
= 8rt
4xy + 7xy
When a=6
2a / 2
= 6
When b=5
b^2
= 25
-3f + 6f - f + 2g
= 2f + 2g
5d + 10x - 4d + d -3x
= 2d + 7x
fy + 3fy - fy - 3fy
= 0
When a=3, b=5, c=10
2a + 3b + c
= 31
When b=3 and c=5
2c - b^2
= 1
ab + 3ab
= 4ab
cd + 4mn + 2cd + 3mn
= 3cd + 7mn
gh - gh - 2gh +tr + 3tr
= -2gh + 4tr