The equation that represents the total number of stamps malik collected is x + y = 212. The equation that represents the difference in the number of foreign and domestic stamps malik collected is: x - y = 34. This is the system of two equations. Malik has a total of 212 stamps: x + y = 212. He has 34 more domestic stamps (x) than foreign stamps (y): x = y + 34. If we rearrange it, we have x - y = 34. So, this is the system of two equations: x + y = 212 and x - y = 34.<span>
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Lets be a price of the calculator - $ a
then , after using the coupon, you need to pay $(a-18)
and after using 15% discount , you need to pay (1-0.15)a=0.85a
then, if
(a-18) will be more than 0.85a, you should prefer 0.15 % discount, because it will be cheaper,
a-18> 0.85a
a-0.85a>18
0.15a > 18
a>120, that means that if the price of the calculator more than $120, 15% discount is better,
but if the price of the calculator is less than $120, you should choose $ 18 coupon.
for example, we have the price of the calculator $100
100-18=82,
100*0.85 =85, coupon is better.
If the price of the calculator $200
200-18=182,
200*0.85=170, so 15% discount is better
if price of the calculator is $120,
120-18=102
120*0.85=102,
it will not matter, what you are going to use, because you are going to pay the same amount of money
your question is incomplete dear check it once
