Top answers

Write 8^2(4^2 / 2^7) in the form 2^x

We know that 8 2 = (2 3 ) 2 = 2 6 and 4 2 = (2 2 ) 2 = 2 4 So we can write the original expression as 2 6 (2 4 /2 7 ) Then using indices laws we get 2 6 (2 -3 ) = 2 3
CC
Answered by Charlotte C. • Maths tutor
3391 Views

Probability: These 6 coins are in a box - 10p, 10p, 10p, 20p, 20p, 50p. Someone takes 2 coins at random. What is the probability that the total value of the two coins is at least 40p?

The question has a number of important points which should be highlighted before beginning. Firstly the fact that the picks are at random. Secondly that the value of the coins must be at least 40p, so a tota...
TP
Answered by Tom P. • Maths tutor
8828 Views

Expand and simplify (x − 4)(2x + 3y)^2

Expand the (2x + 3y)^2 term to give 4x 2 + 9y 2 +12xy Expand (x - 4)(4x 2 + 9y 2 +12xy) to give (4x 3 +9xy 2 + 12x 2 y - 16x 2 -36y 2 - 48xy)
MR
Answered by Mohammed R. • Maths tutor
5253 Views

Solve the simultaneous equations: 4X+6Y=4 and 7X+5Y=12.5

There are two ways of solving this problem: Method 1: substitution. Make X (or Y) the subject of one equation: X= (4-6Y)/4 Substitute this into the other equation: 7/4*(4-6Y) +5Y=12.5 Simplify and rearrange ...
SF
Answered by Sam F. • Maths tutor
3842 Views

A ship sets off on a bearing of 072 degrees from port and travels 3.4km in a straight line. How far north of the ship's starting position is its final position? Give your answer to two decimal places.

From SOHCAHTOA we choose CAH based on trianglecos(theta)= adjacent / hypcos(72)=x / 3.4 3.4cos(72)=xOn calculator find x=1.0506... =1.05 (2dp)
JM
Answered by Jessica M. • Maths tutor
3913 Views