Answer:
x=4 and y=4
Step-by-step explanation:
From first function we have:

And from the second one:

Substitute them:

9514 1404 393
Answer:
sometimes
Step-by-step explanation:
4 + 7 = 11 . . . not a multiple of 7
28 + 7 = 35 . . . a multiple of 7
If you add a multiple of 4 and a multiple of 7, the sum is <u>sometimes</u> a multiple of 7.
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It will be a multiple of 7 when the multiple of 4 used is a multiple of 7, such as 4×7 or 4×14 or 4×21, for example.
Answer:
a⁴b⁴ - c⁴
Step-by-step explanation:
The difference of squares formula states that (a - b)(a + b) = a² - b². In this case, a = a²b² and b = c² so a² - b² = (a²b²)² - (c²)² = a⁴b⁴ - c⁴.