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How do you complete the square?

You start off with a formula in the form y = x 2 + bx. The first step is to add the square of half of the coefficient of x: (b/2) 2 . This allows us to rearrange the formula into (x+ b/2) 2 . However, our fo...
JM
Answered by Jamie M. • Maths tutor
3366 Views

a) Give a balanced equation for the complete combustion of butane, b) Explain how this would change if there was insufficient oxygen present, and explain the problems this causes

C 4 H 10 + 6.5O 2 -> 4CO 2 + 5H 2 O If there is not enough oxygen, incomplete combustion will occur, so CO (carbon monoxide) will be formed, carbon will form soot, and unburnt hydrocarbons will be release...
AP
Answered by Abigail P. • Chemistry tutor
11328 Views

How do I use verbal aspect in the past tense?

In Russian, verbal aspects are used to indicate the state of the action that you are talking about. In English we can distinguish between ongoing actions (e.g. “I have been reading a book”) and completed act...
EB
Answered by Emma B. • Russian tutor
1960 Views

How many times further away from the pivot point of a seesaw does someone of double the weight have to sit in order for the it to balance?

Sum of moments in equilibrium must equal 0. The sum of clockwise moments must equal the sum of anticlockwise moments. W1 is the force exerted on the seesaw by the heavy person at distance D1 from the pivot a...
RM
Answered by River M. • Physics tutor
3476 Views

How can I factorise 2(x^2)+3x+1=0 ?

This quadratic equation is in the form ax^2+bx+c=0 (a=2, b=3, c=1), where there is a coefficient in front of X 2 term. First we have to multiply a and c. we then have to find two numbers z and y which multip...
JR
Answered by Jonathan R. • Maths tutor
3398 Views