2n - 5 = $\frac{1}{2}$n

Get rid of the fraction by multiplying both sides of the equation by the denominator (2).

2 x 2n - 2 x 5 = 2 x $\frac{1}{2}$n

4n - 10 = 1 x n
4n - 10 = n
4n - n = 10
3n = 10

Divide both sides by 3 so that n can stand alone

n = $\frac{10}{3}$ = 3$\frac{1}{3}$

Get rid of the denominator (2) by multiplying each part of the equation by 2

2 x (x-1) = 1(x+2)

Expand the bracket

2 x x - 1 x 2 = 1 x x + 1 x 2

2x - 2 = x + 2

2x - x = 2+2

x = 4

Change the decimal to fraction by multiplying both the numerator and the denominator by 1n0s where n0s means number of zeros to attach to 1 for the multiplication

n is the number of times to move the decimal point to get a whole number

To change 10.5 to 105, you will realize we have to move the decimal to the right once (1 time)

Hence we can multiply 10.5 by 10/10

10/10 = 1 so doesn't affect the figure but for the sake of simplication that's why we put it so

10.5 = 10.5 x 10/10 = 105/10

The updated equation will now be:

Now cross multiply

n x 10 = 105 x 100

Divide both sides by 10 to make n the subject

10 cancels each other and the zeros cancel each other

n = 105 x 10 = 1050

Since the number outside the bracket are the same in both sides of the equation, the values inside the bracket are also the same

Thus if a x b = a x c, implies that b = c

12+18 = 15+k

30 = 15 + k

30 - 15 = k

15 = k

Solve for the value of x (Make x the subject)

2x – 1 = 5
2x = 5 + 1
2x = 6

Divide both sides by 2

2x/2 = 6/2

x = 3

NOTE: When negative crosses the equal to sign, it becomes positive, hence the -1 becomes +1 when it moves to the right hand side.

Solve: (1-x)÷3<4

Get rid of the denominators by multiplying both sides of the equation by L.C.M. Every number is divisible by 1.

The L.C.M of 3 and 1 is 3

Divide both sides by -1.

NOTE: When dividing x by negative, the sign must change x > -11

Alternatively you can take the x to the right hand side and the numbers to the left.

Which reads -11 is less than x

Hence if -11 is less than x means x is also greater than – 11.

Hence x > -11

Let’s test

Hence x > -11 is correct

Testing x < -11 is option too. Numbers less than -11 are -12, -13, -14, -15 etc.

when x = -12