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Solve the equation x^2+17x+12=-3x^2 to the nearest tenth.

User Zxzak
by
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1 Answer

0 votes

Answer:


x=-(17)/(8)+(√(97) )/(8) or
x=-(17)/(8)-(√(97) )/(8)

Explanation:


x^2+17x+12=-3x^2

Add
3x^2 on both sides.


x^2+17x+12+3x^2=-3x^2+3x^2


x^2+17x+12+3x^2=0

Combine like terms;


4x^2+17x+12=0

Use the quadratic formula;

a=4

b=17

c=12


x=\frac{-b\frac{+}{}√(b^2-4ac) }{2a}


x=\frac{-(17)\frac{+}{}√((17)^2-4(4)(12)) }{2(4)}


x=\frac{-17\frac{+}{}√(289-192) }{8}


x=\frac{-17\frac{+}{}√(97) }{8}


x=-(17)/(8)+(√(97) )/(8) or
x=-(17)/(8)-(√(97) )/(8)

User Nidia
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