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How do you solve the quadratic equation x^2+7x+12=0

To solve quadratic equations we first need to factorise the equation into brackets. We can do this by looking at the numbers in the quadratic equation. The only number that isn't an x coefficient is the 12, ...
CD
Answered by Charlie D. • Maths tutor
10822 Views

How do you add and multiply surds?

When you add and subtract surds, the numbers inside the square root must be the same. You add/ subtract the number outside the square root. e.g. 2√5 + 7√5 = 9√5, however 2√5 + 7√3 cannot be added. when you m...
GC
Answered by Grace C. • Maths tutor
74713 Views

Solve the simultaneous equations: x^2 + y^2 = 25 and y − 2x = 5

x 2 +y 2 =25, y-2x= 5 y = 5+2x -----> y 2 = (5+2x) 2 = 25 + 20x +4x 2 x 2 + 4x 2 + 20x + 25 = 25 5x 2 + 20 x = 0 x = 0 y = 5+(2*0) y=5
AG
Answered by Alex G. • Maths tutor
26835 Views

a) Factorise the following expression (x^2)-49 b) Differentiate the following equation y = (x^2) - 49 and find the stationary points of the equation

a) (x+7)(x-7) b) y = (x^2) - 49 y' = 2x 0 = 2x x = 0 y = (0^2) - 49 y = -49, x = 0
TG
Answered by Thomas G. • Maths tutor
3652 Views

Show that (sqrt(3) + sqrt(75))^{2} = 108

The key here is to simplify the left hand side. There are two different approaches to take here, one slightly faster but both perfectly legitimate. First approach: Remember the formula (a + b)^{2} = a^{2} + ...
CB
Answered by Callum B. • Maths tutor
6727 Views