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The number of real solutions to the quadratic equ
5a² + 30a + 45 = 0

The number of real solutions to the quadratic equ 5a² + 30a + 45 = 0-example-1
User Anycorn
by
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2 Answers

2 votes

Answer:

two equal, real solutions

Explanation:

The quickest way to determine this is to find the discriminant b^2 - 4ac. If this determinant (D) is > 0, the quadratic has two different real roots; if + 0, the quadratic has two equal real roots, and if < 0, the quadratic has two imaginary or complex roots.

Here a = 5, b = 30 and c = 45. The discriminant is

30^2 - 4(5)(45) = 900 - 900 = 0

and so this quadratic has two equal, real solutions.

User LZW
by
4.6k points
3 votes

The answer is 1.

There is one unique real solution, which is x = -3.

Hello, please consider the following.


5a^2+30a+45 = 0\\\\<=> 5(a^2+6a+9)=0\\\\<=> a^2+6a+9=0\\\\<=> a^2+2*3*a+3^2=(a+3)^2=0\\\\<=>\boxed{a=-3}

Thank you

User Darin Dimitrov
by
5.0k points