Arlene had some blackberries. she gave 216 to her teachers. then she dropped 12. later, she ate 18. finally, she gave half of what she had to her friend. now, she has 15.how many did she have to start

the number of BlackBerry that Arlene had initially was 276

Step-by-step explanation:

Let x represent the number of BlackBerry that Arlene had initially.

She gave 216 to her teachers. This means that she is left with x - 216

Then she dropped 12. This means that she would be left with x - 216 - 12 = x - 228

Later, she ate 18. This means that she would be left with x - 228 - 18 = x - 246

Finally, she gave half of what she had to her friend. This means that the amount that she gave to her friend is (x - 246)/2 and the amount that she has left would be

(x - 246)/2

Now, she has 15. This means that

(x - 246)/2 = 15

x - 246 = 2 × 15 = 30

x = 30 + 246 = 276

0 is its x and y coordinate