# Math

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Solve the equation
40^2 + 4a = 0

What I did was 4a (10a + 1) = 0 then I'm not sure what to do next...

• Math -

40 ^ 2 + 4a = 0

1600 + 4a = 0

4a = - 1600 Divide both sides with 4

a = - 1600 / 4

a = -400

• Math -

According to what you show in your solution, your equation was probably

40a^2 + 4a = 0
then
4a(10a + 1) = 0
so 4a = 0 or 10a+1 = 0
a = 0 or a = -1/10

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