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3 years ago

Please help math

2 answers:

8 0

$\displaystyle\\
15(2a - 2) = 5(a^2 -1) \\ \\ 
30a - 30 = 5a^2-5\\\\
-5a^2 + 30a -30 + 5 =0\\\\
-5a^2 + 30a -25 =0 ~~~~~\Big| \times (-1) \\\\
5a^2 - 30a +25 = 0~~~~~\Big| : 5 \\\\
a^2 - 6a +5 = 0 \\ \\ 
a_{12}= \frac{-b\pm \sqrt{b^2-4ac}}{2a}= \frac{6\pm \sqrt{36-20}}{2}= \frac{6\pm \sqrt{16}}{2}=\frac{6\pm 4}{2}= \boxed{3\pm 2} \\ \\ 
a_1 = 3+ 2 = \boxed{5}\\\\
a_2 = 3-2 = \boxed{1}$

ELEN [110]3 years ago

7 0

Answer:

Step-by-step explanation:

i took the test

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2 years ago

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2 years ago

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den301095 [7]

Answer:

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2 years ago

Please help i have 2 questions thank you very much.

Rudik [331]

Hello!

Question 1
We first have to convert everything to yards since the concrete is charged by the cubic yards

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5 * 5 * 0.08333 = 2.08325

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The answer is C) $95.83
------------------------------------------------------------------------------------------------------
Question 2

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<span>7167.999 = lw * 112
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Hope this helps!

8 0

3 years ago