Answer:
c
Step-by-step explanation:
if I understand this right, then the expression is
2×sqrt(28) - 5×sqrt(63)
let's look for squared factors in the numbers under the square roots.
28 = 4×7 (4 is a squared number)
63 = 9×7 (9 is a squared number)
so,
2×sqrt(4×7) - 5×sqrt(9×7) =
= 2×2×sqrt(7) - 5×3×sqrt(7) = 4×sqrt(7) - 15×sqrt(7) =
= (4 - 15)×sqrt(7) = -11×sqrt(7)
<h3>
Answer: 6 hours</h3>
Work Shown:
(90 lawns)/(45 hours) = (12 lawns)/(x hours)
90/45 = 12/x
2 = 12/x
2x = 12
x = 12/2
x = 6
It takes 6 hours to mow 12 lawns.
For a perfect square
b² = 4*a*c
Comparing ax² + bx + c = 0 to x² + bx + 16
a = 1, c = 16
<span>b² = 4*a*c
</span>
<span>b² = 4*1*16
</span>
<span>b² = 64
</span>
b = √64
b = 8
The value of b = 8.
Answer:
The degree of is 4.
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