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PLEASE HELP ME ANY ANSWERS PLEASEEEE I DONT UNDERSTAND THIS!!!!!) Marina wants to purchase a rosebush for d dollars at a garden store. She has a coupon good for $5 off her purchase, and the store is having a 10% off sale.

PART A
write two different, equivalent expressions for how much the rosebush will cost if the coupon is applied first and the 10% discount second.
PART B
write an expression for how much the rosebush will cost if the 10% discount is applied first and the coupon is applied second.
PART C
which order will save marina more money? explain your reasoning.

User Wuliang
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1 Answer

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PART A:
0.9(d-5) and
0.9d-4.5

If we apply the coupon first, we have
d-5, because we are subtracting 5 dollars from the total price. Then, if we apply the discount, we get
0.9(d-5). It is a 10% discount, which means the price will end up being 90% of the original price, so we need to multiply the price by 0.9. To get the second equation, I distributed the 0.9 (multiplied it by both parts of the equation in parentheses) to get
0.9d-4.5.

PART B:
0.9d-5

If we apply the discount first, we get
0.9d. Then, when we apply the coupon, we subtract 5 dollars from that price, getting
0.9d-5.

PART C: Discount, then coupon.

To figure out which order will save more money, we look at the simplified equations for each order. In the first order, we end up subtracting 4.5 from
0.9d, and in the second order, we end up subtracting 5 from
0.9d. In the second order, we are subtracting more money, so the price will be lower and she will save more money.

User Heads
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