Question

x^2 +x-20=0 solve the following by competing the square method ​

Answer 1

Answer:

x=4,-5

Step-by-step explanation:

x²+x-20=0

x²+x=20

thus, adding [1/2 of coefficient of x]²=[1/2×1]²=1/4

x²+x+1/4=20+1/4

[x+1/2]²=81/4

taking square roots both the sides

x+1/2=±√[81/4]

x+1/2=±[9/2]

thus,

x=9/2-1/2=8/2=4

x=-9/2-1/2=-10/2=-5