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4 votes
Problem
Solve for xxx.
5x^2 + 60x + 180 = 05x
2
+60x+180=0

User TiLithitum
by
5.9k points

1 Answer

9 votes

Answer:

x = -6

Explanation:

5x² + 60x + 180 = 0

5 x 180 = 900

you need 2 numbers that multiplies into 900 and adds into 60. these numbers are 30 and 30. now we can rewrite it

5x² + 30x + 30x + 180 = 0.

split it in half and factorise

5x(x + 6) + 30(x + 6) = 0

this means the brackets are:

(5x + 30)(x + 6) = 0

5x + 30 = 0

5x = -30

x = -6

x + 6 = 0

x = -6

therefore, x = -6.

User Olga Mu
by
5.1k points