Top answers

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
75103 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
26938 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
3732 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
6808 Views

What is the difference between simple and compound interest?

Simple interest means the amount of money increases by the same amount each year, compound interest means the amount of money increases by the same proportion each year. For example if you deposited £100 in ...
JS
Answered by James S. • Maths tutor
13903 Views