Answers

2014-06-29T12:29:09+08:00
SOLVING QUADRATIC EQUATIONS BY EXTRACTING SQUARE ROOTS
4 x^{2} -225=0
 \sqrt{4x^2}= \sqrt{225}
 \frac{2x}{2}= \frac{15}{2}
x= +or- \frac{15}{2}
 \left \{ {{x= \frac{15}{2} } \atop {x= \frac{-15}{2} }} \right.

(s-4)^2-81=0
 \sqrt{(s-4)^2}= \sqrt{81}
s-4= +or-9
s=4+9
s=13
s=4-9
s=-5
 \left \{ {{s=13} \atop {s=-5}} \right.

(x-7)^2=289
 \sqrt{(x-7)^2}=  \sqrt{289}
x-7=+or-17
x=7+17
x=24
x=7-17
x=-10
 \left \{ {{x=24} \atop {x=-10}} \right.

SOLVING QUADRATIC EQUATIONS BY FACTORING

3 x^{2} -5x=2
3 x^{2} -5x-2=0
(3x+1)(x-2)=0
3x+1=0
x-2=0
 \frac{3x}{3}= \frac{-1}{3}
x=2
 \left \{ {{x= \frac{-1}{3} } \atop {x=2}} \right.

8 x^{2} -2x-1=0
(2x-1)(4x+1)=0
2x-1=0
4x+1=0
 \frac{2x}{2}=  \frac{1}{2}
 \frac{4x}{4}=  \frac{-1}{4}
 \left \{ {{x= \frac{1}{2} } \atop {x= \frac{-1}{4} }} \right.

y^2-16=0
(y-4)(y+4)=0
y-4=0
y+4=0
 \left \{ {{y=4} \atop {y=-4}} \right.

P.S. I hope I wasn't late, it's kinda long so,yeah... I hope I helped. ^_^ \/

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thank you so much po :D
You're welcome po ^_^