Solve x^2+4x-5=0 by completing the square.
x^2+4x-5=0(x+2)^2-(2)^2-5=0subtract 2^2 as (x+2)^2 = x^2+4x+4 when we want x^2+4x(x+2)^2-4-5=0(x+2)^2-9=0(x+2)^2=9square root both sidesx+2=+/-3x=-2+/-3x=-2+3 or x=-2-3x=1 or x=-5
EM
Related Maths GCSE answers
All answers ▸Solve the simultaneous equations: 3x − y = 23 2x + 3y = 8
Dividing Fractions
Which of these lines are parallel to y=2x+3? Which are perpendicular? Options: 1) y=5x-4, 2) y=-1/3x+3, 3) y=-1/2x-1, 4) y=2x-2/3
A(0,2) and B(6,5) are two points on the straight line ABCD. If AB=BC=CD find the coordinates of the point D