How do you simplify expressions involving different powers?

Let's answer the question by solving an example:

Take (8x2 * 5x4 * 2y3)/(20x3). Firstly, let's take a look at the first bracket and rearrange it so we have both numbers and variables grouped together:

= (8 * 5 * 2 * x2 * x4 * y3)/(20x3). We can perform such operation because multiplication is commutative - the order does not matter.

= (80 * x2 * x4 * y3)/(20x3). Secondly, to further simplify the expression in first brackets, we have to multiply x2 and x4. To multiply powers of the same number (variable), we simply add the exponents (the "powers" or the numbers in index)

=(80 * x2+4 * y3)/(20x3) = (80x6 * y3)/(20x3) Now we can write this as a fraction and reduce it (80/20=4), so we are left with

= 4(x6 * y3)/(x3). Now, when dividing powers of the same number/variable, we, quite analogically to the previous example, substract one exponent from another to get:

= 4 * x6-3 * y3 = 4 * x3 * y3, which cannot be simplified further and is our final answer.

Answered by Patryk W. Maths tutor

3041 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Tim stretches by leaning against a pole that is 1.5 metres tall and at a right angle to the floor. Tim is standing 0.5 metres away from the pole, how tall is Tim; leaving your answer in terms of metres? (2.d.p)


Make "a" the subject of the following equation: 2b = (3a+4)/(c-a)


How to solve simultaneous equations with two unknowns?


Nicky buys a blender. 20% VAT is added to the price of the blender so Nicky has to pay £180. What is the price of the blender with no VAT added?


We're here to help

contact us iconContact usWhatsapp logoMessage us on Whatsapptelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo
Cookie Preferences