Algebra

Question 1

How do you rearrange a formula.

Answer 1

1. Always do the same thing to both sides of the
   formula.
2. To get the letter on its own you have to do the opposite to get rid of the numbers. ( - is + and x is ÷)
   3) keep going until the letter is on its own.

Question 2

What do you do if you want to find out what x is? e.g 9x = 27

Answer 2

Find out what x is on its own my doing the oppisite to what is in the equation with x e.g 27÷ 9

Question 3

if both numbers in an equation are negative or positive what do they become?

Answer 3

They become positive.

Question 4

If numbers in an equation are positive and a negative what do the become?

Answer 4

They become negative.

Question 5

How do you do the opposite to squaring something?

Answer 5

You find the square root of the number.

Question 6

What do you do if the minus is outside the brackets when expanding single brackets by multiplication?

Answer 6

Remember to include the minus sign in the equation e.g if the number inside the bracket is positive you reverse it to be negative.

Question 7

What does does 3a mean?

Answer 7

3 x a or a + a +a.

Question 8

What does A cubed mean?

Answer 8

It means A x A x A.

Question 9

What does FOIL stand for?

Answer 9

First = multiply the first term in each bracket together
Outside = multiply the outside terms (i.e. the first term in the first bracket and the second term in the second bracket)
Inside = multiply the inside terms ( the second term in the first bracket by the first term in the second bracket)
Last = multiply the second term in each bracket together.

Question 10

What does the F stand for in FOIL?

Answer 10

First = multiply the first term in each bracket together
e.g. (n - 1) (2n +5) this first step would be n x 2n

Question 11

What does the O stand for in FOIL?

Answer 11

Outside = multiply the outside terms
e.g. (n - 1) (2n +5) this step would be n x 5

Question 12

What does the I stand for in FOIL?

Answer 12

Inside = multiply the inside terms
e.g. (n - 1) (2n +5) this step would be -1 x 2n

Question 13

What does the L stand for in FOIL?

Answer 13

Last = multiply the second term in each bracket together
e.g. (n - 1) (2n +5) this step would be -1 x 5

Question 14

What is factorising?

Answer 14

Putting brackets back into an equation by doing the inverse of an equation.

Question 15

How do you factorise?

Answer 15

1. Take out the biggest number that goes into all the terms.
2. For each letter in turn, take out the highest power that will go into every term.
3. Open the brackets and fill in all the bits needed to reproduce each term.
4. Check your answer by multiplying out the brackets again.

Question 16

How do you know what to put at the front of the brackets?

Answer 16

This should be the common factor of the numbers in the original expression e.g. 10x + 25y = 5(2x + 5y) because 5 is the common factor of 10 and 25.

Question 17

How do you take out a letter when factorising?

Answer 17

You can take away one of its powers and move it somewhere else e.g. 4x^2 + 8x = 4x(x+2).