Solve the quadratic equation: 5x2+8x+2

Here you need to use the quadratic formula, it cannot be solved by expanding out the brackets. In the formulae for which can be found on the formulae sheet. In this case a=5, b=8 and c=2.

This gives: x=(-8±√(82-(4x5x2)))/(2x5)

This simplifies to x=(-8±√24)/10

The plus or minus sign shows there are two possible solutions.
For x=(-8+√24)/10, x=0.3
For x=(-8-√24)/10, x=-1.3

LP

Related Maths GCSE answers

All answers ▸

A plane travels at 213 miles per hour. Work out an estimate for how long, in seconds, the plane takes to travel one mile.


Evaluate 5/(x−1)+2/(x+4)


how do you convert repeating decimals into a fraction?


Let f(x) = x^2 - 1. A vertical translation of 3 and a horizontal translation of -2 is applied. Write the new function g(x) in the form g(x) = ax^2 + bx + c