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If x = 1 is a common root of ax² +ax + 2 = 0 and x² + x + b = 0 , then ab =

User Nuno Tomas
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1 Answer

6 votes

Answer:

ab = 2

Explanation:

Given equations

ax² +ax + 2 = 0

x² + x + b = 0

root of both the equation

x= 1

then we can plug in x = 1 in both the equation

ax² +ax + 2 = 0 x² + x + b = 0

a*1² +a*1 + 2 = 0 1² + 1 + b = 0

a +a + 2 = 0 1 + 1 + b = 0

2a + 2 = 0 2 + b = 0

2a = - 2 b = -2

a = -2/2 = -1

Thus,

a = -1

b = -2

a*b = -1*-2 = 2

ab = 2

User SOG
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