Vertical angles<span> are the angles opposite each other when two lines cross, so
</span>∠AOB and ∠DOC are vertical.
Answer:
Step-by-step explanation:
Use the following formula:
slope: 
Let:

Plug in the corresponding numbers to the corresponding variables:

is your answer.
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Let there be 2x science and 5x art books
<span>science books sold = 2x × 0.2 = 0.4x </span>
<span>science books unsold = 2x – 0.4x = 1.6x </span>
<span>art books sold = 5x × 0.2 = x </span>
<span>art books unsold = 5x – x = 4x </span>
<span>total books unsold = 1.6x + 4x = 5.6x </span>
<span>5.6x = 2240 </span>
<span>x = 400 </span>
<span>2x science = 800 </span>
<span>and 5x art books = 2000 </span>
HETY is a parallelogram.
HT and EY are diagonals. We know that diagonals divides the parallelogram into two equal parts.
So ar(HET) = ar(HTY)
And, ar(HEY) = ar(EYT) now, in AHET, diagonal EY bisects the line segment HT and also the AHET,
∴ar(AHOE) = ar(AEOT)
Similarly in AETY
ar(ΔΕΟΤ) = ar(ΔΤΟΥ)
And in AHTY,
ar(ATOY) = ar(AHOY)
That means diagonals in parallelogram divides it into four equal parts.
Hence Proofed.
22,200
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