Answer:
95%
Step-by-step explanation:
Answer:5 days
Step-by-step explanation:
16 divided by 4=4 postcards a day
20 divided by 4=5
5 days in total
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Answer:
distance=rate*time
2520=(r)(3)+(r+90)(3) (they both travel for 3 hours)
2520=3r+3r+270
2520-270=6r
2250=6r
r=2250/6
r=375 mph
r+90=375+90=465 mph
Step-by-step explanation:
81 a² - 25
is a difference of two squares and its factors are (9a + 5z³) and (9a - 5z³)
Step-by-step explanation:
The difference of two squares is a binomial of two terms each term is a square and the sign between the two terms is (-), its factorization is the product of two identical binomials with different middle signs
- a² - b² is a difference of two squares
- a² - b² = (a + b)(a - b)
∵ The binomial is 81 a² - 25
∵
= 9
∵
= a
∴ 
∵
= 5
∵
= z³
∴ 
- The two terms have square root
∵ The sign between them is (-)
∴ 81 a² - 25
is a difference of two squares
∵ Its factorization is two identical brackets with different
middle signs
∵ 81 a² = 9a × 9a
∵ 25
= 5z³ × 5z³
- The terms of the two brackets are 9a and 5z³
∴ 81 a² - 25
= (9a + 5z³)(9a - 5z³)
81 a² - 25
is a difference of two squares and its factors are (9a + 5z³) and (9a - 5z³)
Learn more:
You can learn more about the difference of two squares in brainly.com/question/1414397
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