Answer:
167.9166459
Step-by-step explanation:
Difference of two squares will be
16y^2 -x^2 = (4y -x)(4y +x)
so the second choice
Answer:
2.6%
Step-by-step explanation:
Given the current CPI = 231.56
Previous CPI (CPI a year ago) = 225.3
Rate of inflation over the past year = current CPI - previous CPI/previous CPI × 100%
Rate of inflation = 231.56-225.3/225.3 × 100%
5.86/225.3× 100%
= 2.6%
Rate of inflation over the past year will be 2.6%
Answer:
Step-by-step explanation:
Question (1)
x² + 10x + 12
= x² + 2(5x) + 5² - 5² + 12
= [x² + 2(5x) + 5²] - 5² + 12
= (x + 5)² - 25 + 12 [Since, a² + 2ab + b² = (a + b)²]
= (x + 5)² - 13
Question (2)
y² - 6y - 15
= y² - 2(3y) - 15
= y² - 2(3y) + 3² - 3² - 15
= [y² - 2(3y) + 3²] - 3² - 15 [Since, a² - 2ab + b² = (a - b)²]
= (y - 3)² - 3²- 15
= (y - 3)² - 9 - 15
= (y - 3)² - 24
The first expression is equivalent to B
The second expression is equivalent to A
The third expression is equivalent to C
You are basically adding like terms. For example for the first expression, it is 7x^2 + 2x^2, which equals 9x^2. Remember since you're adding, do not add the exponents.
