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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 1...

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 yo...

x²+y²=25, y-2x= 5 y = 5+2x  -----> y² = (5+2x)² = 25 + 20x +4x² x² + 4x² + 20x + 25 = 25 5x² + 20 x = 0 x = 0 y =...

a) (x+7)(x-7) b) y = (x^2) - 49 y' = 2x 0 = 2x x = 0 y = (0^2) - 49 y = -49, x = 0

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}...