If xy>0, then the points of P(x, y) lies...

If xy>0, then the points of P(x,y) lies in Quadrant I and III

According to the given condition;

This means that the product of x and y is a positive number.

Hence, either both x and y-coordinates are positive or are both negative

Hence, only points in the Quadrant I have positive x and y coordinates Or Quadrant III in which case all x and y values are negative.

Read more on Cartesian plane;

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In Quadrant I or III

Step-by-step explanation:

We know if the sign was not showing closed inequality facing other way

xy < 0 would be in the 2nd or 4th quadrant.

If xy = 0  then either xy or both are on the x or y axis

But if xy>0 then they are in quadrant I or III

you would need to know all the numbers that are on there

step-by-step explanation:

answer:   expression= p+p*d%

price reduction + sale price = $625

sale price: $p+$p*d%

where d% is the percentage of discount

step-by-step explanation:

original price = p

price went down by $150 price reduction $p*d%

sale price= $ 475

therefore the price before sale is: $625

and the expression that shows the price before sale is: p+p*d%