Question

Y2+7y-9=0
Find the following quadratic equations by using formula method

Answer 1

Answer:

On comparing with ax^2 +bx +c

a= 1,b=7,c=9

By using the formula,

x=-b+-√b^2+4ac/2a

-7+-√7×7+4.1.9/2.1

-7+-√49+36/2

-7+√85/2. , -7-√85/2

The roots of the given equation are -7+√85/2,-7-√85/2

Answer 2

Answer:

x=[7 plus or minus root(13)]/2

Step-by-step explanation:

y^2+7y-9=0

a=1

b=7

c=-9

x=[-b+(D)^1/2 ]/2a

x=[-b-(D)^1/2 ]/2a

D=b^2-4ac

D=49-4(1)(-9)

D=49-36

D=13

x=[-7+(13)^1/2]/2

x=[-7-(13)^1/2]/2