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Solve the following for x:

2х2 + 9x + 9 = — 1
х=4 or x=5
Ox=-5/2 or x=-2
Ox=2/5 оr x=-2
х=2 or x=9

User Gradbot
by
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1 Answer

3 votes

Explanation:

2x(squared)+9x+9=—1

2x(squared)+9x+9+1=0

2x(squared)+9x+10=0

multiply the coefficient of x and 10=2x10=20

2x(squared)+9x+10=0

look for two numbers that when added gives 9and when multiplied gives 20

2x(squared)+5x+4x+10=0

(2x(squared)+5x)+(4x+10)=0

find the number and letters that are common in the equations

x(2x+5)+2(2x+5)=0

(x+2) (2x+5)=0

x+2=0

collect like terms

x=0-2

x=-2

2x+5=0

collect like terms

2x=0-5

2x=-5

divide both sides by 2

2x/2=-5/2

x=-5/2

so x=-2 and -5/2

User Keith Smiley
by
3.7k points