If the TV is 70% off, then that means she paid 30% of the original cost. If 30% of the original cost is $120, then...
30% * x = 120
.30x = 120
x = 120/.30
x = 400
The original cost was $400
The answer is: x² – 6x + 9 = 0 .
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Explanation:
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Given: (x – 3)² = 0 ; write as: general form: "ax² + bx + c = 0"; a ≠ 0 .
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Note: </span>(x – 3)² = (x – 3)(x – 3) = x² – 3x – 3x + 9 = x² – 6x + 9 ;
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Rewrite: (x – 3)² = 0 ; →
as: x² – 6x + 9 = 0 ; which is our answer.
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→ x² – 6x + 9 = 0 ; is in "general form", or "standard equation format"; that is: " ax² + bx + c = 0 "; (a ≠ 0) ;
→ in which:
a = 1 (implied coefficient, since anything multiplied by "1" is that same value);
b = -6;
c = 9
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Answer:
Given: 
.
Assuming that 
, 
while 
.
Step-by-step explanation:
By the Pythagorean identity 
.
Assuming that , 
.
Rearrange the Pythagorean identity to find an expression for 
.
.
Given that :
.
Hence, 
would be:
.
