how do I solve the equation x^2 + 7x + 11 = 0, to 3dp?


This is a quadratic equation and there are three ways to solve one. This question specifies that the answer should be left to three decimal places. This tells you that you can not factorise, as your answer would be an integer. The linear x term, 7x, has a odd coefficient, therefore completing the square is not advised. The best method for solving this is by using the quadratic formula. This involves substituting the three coefficients of the quadratic equation into a set formula to find the roots/ solution to the equation. The formula is:x = (-b+/- squareroot(b^2 - 4ac))2*aWhere a is the x^2 coefficient, b is the x coefficient and c is the constant term.The +/- indicates that there are two solutions. The first being when a + is used and the second when a - is used. The two values the calculator returns should be rounded to 3 decimal places and then are the solutions to the question.

JD
Answered by Jamie D. Maths tutor

4114 Views

See similar Maths GCSE tutors

Related Maths GCSE answers

All answers ▸

Simplify √48


How can I find x and y?


The point P has coordinates (3, 4) The point Q has coordinates (a, b) A line perpendicular to PQ is given by the equation 3x + 2y = 7 Find an expression for b in terms of a.


solve 2x^2+4x-7=0


We're here to help

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

© MyTutorWeb Ltd 2013–2025

Terms & Conditions|Privacy Policy
Cookie Preferences