We can write this as the difference of squares:
(5b⁸+8c)(5b⁸-8c)

To write as the difference of squares, take the square root of each term first:
√25b¹⁶ = 5b⁸; √64c² = 8c

Now we write this as a sum in one binomial and a difference in the other:
(5b⁸+8c)(5b⁸-8c)

4 0

3 years ago

Rob's first four test scores are 80, 85, 100 and 85. What does he have to score on the last test in order to have a test average

faust18 [17]

Answer:

100

Step-by-step explanation:

85 +80+100+85+x(the unknown),/the number of numbers ie 5

350+x/5=90

350+x=90 * 5

350+x=450

x=450-350

x=100

6 0

3 years ago

Teresa purchased a prepaid phone card for $20. Long distance calls cost 16 cents a minute using this card. Teresa used her card

shtirl [24]

Answer:

33 minutes. 20- 14.72=5.28

Step-by-step explanation:

20- 14.72=5.28. then divide 5.28 by .16(cents per minute) to get 33 minutes

8 0

3 years ago

(3-5i)(2+9i)+(7+2i)(7-2i)

kondor19780726 [428]

$i^{2} = -1$

-----------------------------------------

$(3-5i)(2+9i)+(7+2i)(7-2i) = \\ \\ = 6 + 27i - 10i - 45i^{2} + 49 - 14i + 14i - 4i^{2} = \\ \\ =55 + 17i + 45 + 4 = \boxed{104 + 17i}$

7 0

3 years ago