Hello,
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Answer C
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x^3+7^3=(x+7)(x²-7x+49) A: False (+14)
x^3+8^3=(x+8)(x²-8x+64) B:False (+8x)
x^3-10^3=(x-10)(x²+10x+100) D:False (-10x)
Well, to write the definition of "Perpendicular lines form right angel" using "if and only if". the sentence would become :
<em>
</em><em>Two lines are perpendicular if and only if they form a right angle
</em><em>
</em><em />Hope this helps
