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How do I balance equations?

Balancing equations will become natural if you do it long enough but takes a bit of practice and can be tedious! It can be a bit of trial and error at times. It is important to remember that numbers of el...

Answered by Aysha M. • Chemistry tutor

2602 Views

Solve the simultaneous equation, 3x + y = 8 and x + 3y = 12, to find a value for x and y.

Re arrange one of the equation to get a single variant answer. So, x = 12 - 3y. Substitute this into the other equation, so 3 (12-3y) + y = 8. Expand this equation to form 36 - 9y + y = 8. Collect the y t...

Answered by Grace R. • Maths tutor

6499 Views

Show that (x + 4)(x + 5)(x + 6) can be written in the form ax3 + bx2 + cx + d where a, b, c and d are positive integers.

=(x+4)(x²+6x+5x+30)=(x+4)(x²+11x+30)=x³+11x²+30x+4x²+44x+120=x³+15x²+74x+120

Answered by Jiawen Z. • Maths tutor

2913 Views

Explain why an extensive network of capillaries and ventilation of the lungs helps to maximise the effectiveness of gas exchange.

The capillaries deliver blood that has high carbon dioxide levels and low oxygen levels and take away blood that has high oxygen levels and low carbon dioxide levels. This means there is always a concentr...

Answered by Annabel C. • Biology tutor

6580 Views

Compare and contrast the structure and bonding of diamond and graphite.

1 mark each for each of these points:similarities:only contain carbon atomsatoms covalently bonded to each otherlattice structuredifferences:diamond has four covalent bonds and graphite has threediamond h...

Answered by Annabel C. • Chemistry tutor

4508 Views