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Solve the simultaneous equations x^2 + y^2 = 9 and x+ y = 2. Give your answer to 2.d.p

Label your two equations 1 and 2 respectively. Make x the subject of the second equation, so x=2-y. Substitute x=2-y into x^2+y^2=9, to give (2-y)^2+y^2=9. Expand the brackets using FOIL to give 4-4y+y^2+y^2...
GS
Answered by Georgia S. • Maths tutor
33343 Views

Solve the following quadratic equation: x^2 + 3x + 2 = 0

Step 1: Find factors of the constant (The number with no x attached to it), In our case this is 2. The factors of 2 are: 1 & 2 and -1 & -2. Step 2: The sum of the factors from step 1 must equal the n...
JS
Answered by Jack S. • Maths tutor
4830 Views

Solve for x: 2x^2 + 2x -24 = 0

The general formula of a quadratic is ax^2 + bx + c -> this is a quadratic 2) Factorise using common factor (=2) -> 2(x^2 + x - 12) = 0 3) Factorise the quadratic to (x + m)(x + n): the two numbers (m ...
YZ
Answered by Yige Z. • Maths tutor
11600 Views

Factorise f(x) = x^2+4x+4 and sketch the curve, identifying the roots and minimum point of f(x).

f(x) = (x+2)(x+2) When f(x) = 0, x = -2. f'(x) = 2x + 4 When f'(x) = 0, x = -2, and corresponds to the minimum point. Therefore, the sketch of the curve will be a U-shaped parabola which touches the x-axis a...
OD
Answered by Orlaith D. • Maths tutor
4353 Views

There are 7 white socks and 4 black socks. 2 are taken at random without replacement. What is the probablity that 2 socks of the same colour are taken?

With a more wordy question like this, it is always best to break it up and write down all of the key pieces of information. So we want to work out the probability of picking: white AND white, OR, black AND b...
FH
Answered by Francesca H. • Maths tutor
4075 Views