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Solve: (2a²+5a+2)^1/2=3

2 Answers

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When you have an expression to the power of (1/2) that means the same thing as having a square root.

Lets call a=x

To get rid of the square root we square both sides getting:

2x^2+5x+2= 3^2

Simplifying this we get: 2x^2+5x+2=9

We can subtract 9 from both sides getting: 2x^2+5x-7

Now when we solve for this we can use the quadratic formula:

(-b +/- sqrt(b^2-4ac)) / 2a

a=2 , b=5 , c=-7

Plugging in we end up with : (-5 +/- sqrt(81)) /4

This simplifies to : (-5 +/- 9) / 4 ..... (-5+ (-9))/4 OR (-5-(-9))/4

we have x= -14/4 , 1

User Pcom
by
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Answer:

C a = -7/2 or a = 1

Explanation:

User Nicolas Labrot
by
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