Solve x^2 - 5x - 14 = 0

This is an example of a quadratic equation which we can solve on of two ways as it takes the form ax^2 + bx - c = 0a = 1, b = -5, c = -14 (1) Factorisation which we can do ourselves OR (2) Use the quadratic equation.(1) We need to find two numbers that equate to -5 (b) and multiply to give -14 (c). -7 + 2 = -5 and - 7 x 2 = -14. We therefore know the answer takes the form (x -7) (x+2) = 0. To solve equate each bracket to 0 and derive the value of x: x - 7 = 0 -> x = 7 and x + 2 = 0 -> x = -2. The solutions are x = -2 and x = 7(2) If you can't see this relationship use the quadratic equation - we would run through this in the session

JB

Related Maths GCSE answers

All answers ▸

Solve the simultaneous equations 3x + y = 11 and 2x + y = 8.


The perimeter of a right-angled triangle is 72 cm. The lengths of its sides are in the ratio 3 : 4 : 5 Work out the area of the triangle.


Work out 90% of 130


If a right angled triangle has its longest side 7cm and another side is 4cm then how long is the other side of the triangle? Show your working