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4 years ago

PLZ NEED HELP ASAP!!! One of the solutions to the equation 5x^2+bx+12=0 is − 4/5. Find the other solution.

2 answers:

6 0

The other solution is -3

For ax^2+bx+c=0, the multiplication of the two solutions equals c/a.

Because
ax^2+bx+c=0
X^2+(b/a)x+c/a=(x-x1)(x-x2)=0 if x1 and x2 are the two solutions (roots).
(x-x1)(x-x2)=x^2-(x1+x2)x+x1*x2
The last term x1*x2 equals the last term in X^2+(b/a)x+c/a, so
X1*x2=c/a
(-4/5)*x2=12/5
x2=-3

bonufazy [111]4 years ago

4 0

Answer:

b=-19

Step-by-step explanation:

We know that one of the solutions is x=-4/5

That is a solution to x. So if we plug in (-4/5) into the x in the equation, then it should equal 0.

5(-4/5)^2+b(4/5)+12=0

Now, just solve for b.

5(16/25)+b(4/5)+12=0

(16/5)+(4/5)b+12=0

(76/5)+(4/5)b=0

(4/5)b=-(76/5)

b=-19

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garik1379 [7]

Answer:

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Step-by-step explanation:

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3 years ago

Gaming a video-game designer is using the expression 6n3 in a program to determine points earned, where n is the game level. sim

charle [14.2K]

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5 0

3 years ago

Read 2 more answers

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Anastaziya [24]

I believe the answer is the first one because it’s congruent

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3 years ago

The ratio of credit card sales to cash sales at a store was 8:3. If the store had 144 cash sales, how many more credit card sale

Neko [114]

Answer:

There were 240 more credit card sales than cash sales.

Step-by-step explanation:

By using the ratio 8:3 I was able to determine that if there were 144 cash sales that would mean that there would be 384 credit card sales. However, the question asks "How many more credit card sales were there than cash sales?" Meaning that we need to find the difference. 384-144= 240.

This means that there were 240 more credit card sales than cash sales.

Hope this helped! If you have any questions about what I did please comment!

And if this helped please mark brainliest!

Have a great day!!

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3 years ago

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Norma-Jean [14]

Answer: x=30 (Sorry for wasting your time if the answer is wrong)

Step-by-step explanation:

I did it the lazy way

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(If this is completely wrong then again, sorry)

8 0

4 years ago