Solve the equation by completing the square

Mathematics

1 answer:

Ilya [14]2 years ago

4 0

Answer:

We got the quadratic equation:

$x^2+8x-3=0$

Solving by completing the square:

$x^2+8x-3=0\\x^2+8x+16-16-3=0\\(x+4)^2-16-3=0\\(x+4)^2-19=0\\(x+4)^2=19\\x+4=\pm \sqrt{19} \\x=-4\pm \sqrt{19} \\\\x_{1} =-4+\sqrt{19} \\x_{2} =-4-\sqrt{19}$

Therefore, the answer is letter C

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There are blue, red and yellow marbles in a bag. The probability of choosing a blue marble is 1/8, and the probability of choosi

Ilya [14]

Answer:

3/8

Step-by-step explanation:

So what I did is make 1/2 have a common denominator with 1/8. The common denominator would be 4/8. Then i added 1/8 and 4/8 and got 5/8. Then I subtracted 5/8 and 8/8 because 8/8 would be the 100% chance. Then I got 3/8. So I would then think the chance of getting a yellow marble would be 3/8 chance. I hope I helped :)

3 0

2 years ago

Find the value of 3a^2+2b, If a=3 and b = 4.<br><br>An explanation would be great.

vichka [17]

Answer:

=35

Step-by-step explanation:

3(3) ^2 + 2(4)

= 3(9) + 8

= 35

Where you see a, substitute with 3 and where you see b, substitute with 4

Just follow the steps above.