Download Taking 3 tins from both sides

BALANCING EQUATIONS
We can think of an equation like a set of
scales with two sides that balance. That
means that you can change one side if
you do the same to the other so that it
remains balanced.
Example 1
Solve this balancing equation:
3 tins + 15 kg = 6 tins
15 kg= 3 tins
3 tins = 15 kg
1 tin = 5 kg
+ 15 kg =
(Taking 3 tins from
both sides)
Example 2
Form a balancing equation and solve it.
4 t + 20 = 6 t
20 = 2t (Taking 4 tins from both sides)
2t = 20
t = 10
+ 20 =
Example 3
Draw your own picture if you need it.
4 t + 30 = 10 t
30 = 6t (Taking 4t from both sides)
6 t = 30
1t=5
More Practice
8 t = 3 t + 350
5t + 4 = 34
12 t + 14 = 62
Equations with brackets 1
4(2t + 3) = 44
8t + 12 = 44
(Multiplying out
bracket)
8t = 32
(Subtracting 12 from
both sides)
t=4
(Dividing by 8)
Equations with brackets 2
5(8t - 4) = 220
40t - 20 = 220 (Multiplying out bracket)
40t – 20 ( +20) = 220 ( +20) ( add 20
to
40t = 240
t=6
both sides)
(Dividing by 40)
5(5t + 3) = 165
25t + 15 = 165
25t
= 150
t=6
7(9t - 3) = 294
2(8t - 10) = 44
2(5t - 3) = 8t
3(5t - 8) = 3t
Tins and kg on both sides
3t + 15 = 6t + 3
15 = 3t + 3
(Taking 3t from both sides)
12 = 3t
(Taking 3 from both sides)
t=4
+ 15 kg =
+ 3kg
Form your own equation from the
picture and solve it.
5t + 4 = 2 t + 10
(Taking 2t from both sides)
3t + 4 = 10
(Taking 4 from both sides)
3t =6
t=2
+ 4 kg =
+ 10 kg
1. Take as many of the letter as you can from
both sides.
2. Take as many numbers as you can from both
sides.
3. You should be left with letters on one side
and numbers on the other side.
4. Divide to find what the letter equals.
5. Check by substituting back in to the equation.
The left should equal the right hand side.
6t + 8 = 2t + 12
4t + 8 = 12
4t = 4
t=1
(Taking 2t from both sides)
(Taking 8 from both sides)
More Practice
6t + 51 = 13t + 30
7t + 9 = 4t + 24
5t + 24 = 12t + 10
2(5g + 3) = 6(g + 5)
6t + 51 = 13t + 30
51 = 7t + 30 (Taking 6t from
both sides)
21 = 7t
t=3
(Taking 30 from
both sides)
7t + 9 = 4t + 24
3t + 9 = 24
3t = 15
t=5
5t + 24 = 12t + 10
24 = 7t + 10 (Taking 5t from
both sides)
14 = 7t
t=2
(Taking 10 from
both sides)
Forming expressions and solving
equations
1. Write an expression for the perimeter of this
rectangle using brackets.
3x + 5
2x + 6
2. The perimeter is 38 cm. Write an equation.
3. Solve your equation.
4. Work out the length and width of the
rectangle.
Forming expressions and solving
equations 2
1. Write an expression for the perimeter of this
rectangle.
4b + 7
b+4
2. The perimeter is 62 cm. Write an equation.
3. Solve your equation.
4. Work out the length and width of the
rectangle.
Forming expressions and solving
equations 3
1. Write an expression for the perimeter of this
rectangle.
a+8
2a + 5
2. The perimeter is 4a + 36 cm. Write an equation.
3. Solve your equation.
4. Work out the length and width of the
rectangle.