Answer: He should have used 13 instead of 13i
Step-by-step explanation:
Answer:

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Sentence ⇻ The product of - 11 & - 7 gives 77.
Equation ⇻
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ʰᵒᵖᵉ ⁱᵗ ʰᵉˡᵖˢ
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we have <D = (7x-1)° , <A =(5x+25)°
{ all angles of square is equal to 90° }
<A + <D = 180°
5x + 25 + 7x - 1 = 180°
12 x = 180 - 24
12x = 156
x = 13
<A = (5*13 +25) = 90
< D = ( 7*13-1) = 90
so ABCD is a square
Answer: 8.795 * 10^6 = 8,795,000
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8.795 * 10 = 87.95
8.795 * 10^2 = 879.5
8.795 * 10^3 = 8,795
8.795 * 10^4 = 87,950
8.795 * 10^5 = 879,500
8.795 * 10^6 = 8,795,000