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How do you expand brackets?

Take the expression(x+2)(x+4). Expanding brackets essentially means multiplying them out to get a new expression. In this case, it will have the form x 2 +cx+d, where c and d are numbers to be determined. Th...
JA
Answered by Jan A. • Maths tutor
5262 Views

Describe how water moves from the soil into a root hair cell

Higher concentration of water outside the cell/lower concentration of solutes outside. Water moves into the cell, down a concentration gradient and through a selectively permeable membrane via osmosis
JT
Answered by Jess T. • Biology tutor
5998 Views

Expand and simplify: 4(2x − 3) − 2(x − 5)

4(2x - 3) - 2(x - 5) [Remember that a negative multiplied by a negative makes a positive] 8x - 12 - 2x +10 6x - 2 [Check: can I simplify further? 2(3x - 1)
RC
Answered by Rachel C. • Maths tutor
10549 Views

How would you prove that a substance contains magnesium ions?

Add sodium hydroxide solution to the substance and if a white precipitate is observed that does not dissolve in excess sodium hydroxide then there are magnesium ions in the substance.
RC
Answered by Rachel C. • Chemistry tutor
5497 Views

Why does silver have a high melting point?

Silver contains strong metallic bonds (a lattice of positive ions surrounded by a sea of delocalised electrons) which require large amounts of energy to break, therefore has a high melting point.
RC
Answered by Rachel C. • Chemistry tutor
8425 Views