Solve 2x^2 - 3x - 1 = 0, using the quadratic formula. Give your answer to two decimal places.

To start, let us recall the form of a quadratic equation. y = ax2 + bx + c. When making x the subject of the formula and setting y = 0, we get the quadratic formula, as you may have seen before. x = (-b +- sqrt(b2 - 4ac) )/2a. From our question, we see that a = 2, b = -3, c = -1. We can now plug this into our formula for an answer! We get that x = ( 3 +- sqrt(32 - 4(2)(-1) )/2(2). Solving this and making our root positive we get x = 1.78 (2 dp). Setting our root as negative we get x = -0.28 (2 dp).

JW
Answered by Jason W. Maths tutor

12637 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

5 Footballs and 3 tennis balls cost £2.30, 4 Footballs and 2 tennis balls cost £1.80. What is the total cost of 1 football and 1 tennis ball?


How is frequency density calculated?


How do I multiply two brackets without missing terms when multiplying?


How do I solve a simple simultaneous equation?


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning