To find an average you take the numbers to be averaged and add them together then You take the number and divide it by the number of numbers, in this case 4, and that gives you the average.
on this problem you want to do the opposite. you know the average she wants, an 87, so you multiply it by 4. 87*4=348. then you add the three numbers you have (88,81 and 87) and you get 256.
then you subtract 256 from 348 and you get 92. 92 is your answer to check just add 87+81+88+92=348
348/4=87
87 was the average she wanted.
Hope this helped! good luck :)
If ABCD is a square, then m∠A = 90°.
Therefore we have the equation:
30° + 48° + x° = 90°
78° + x° = 90° |-78°
x° = 12°
Answer: 12
9514 1404 393
Answer:
(1) -5 and -3
Step-by-step explanation:
Descarte's rule of signs tells you the lack of sign changes among the coefficients means there are <em>no positive real roots</em>. That eliminates all answer choices except the first one.
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If you want to go to the trouble, you can factor the equation:
y = (x +3)(x +5)
These factors are zero when x = -5 and x = -3.
Just count, its really simple...its hard to explain using a keyboard tho...sorry i wasnt much help