3 years ago

Complete the square 3x^2+12x=15

1 answer:

3 0

Step-by-step explanation:

$3 {x}^{2} + 12x = 15 \\ 3 ({x}^{2} + 4x) = 15 \\ {x}^{2} + 4x = 5 \\ {x}^{2} + 4x = 5 \\ {x}^{2} + 4x + 4 = 5 + 4 \\ {x}^{2} + 4x + 4 = 9 \\ {x}^{2} + 4x + {2}^{2} = {3}^{2} \\ \red{ \bold{ (x + 2)^{2} = {3}^{2}}} \\$

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3 years ago

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Step-by-step explanation:

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3 years ago

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Let's use the "elimination by addition/subtraction" method to solve this system for x and y.

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-----------------------
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3 years ago

A garden table and a bench cost $672 combined. The garden table costs $78 less than the bench. What is the cost of the bench?

KonstantinChe [14]

Answer:

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Step-by-step explanation:

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