Solve the following system of equations

Mathematics

1 answer:

Katyanochek1 [597]3 years ago

8 0

Answer:

x = -9

y = -3

Step-by-step explanation:

We can first multiply the 2nd equation by -6, so we have:

$-6*[-0.8x+0.4y=6]\\=4.8x-2.4y=-36$

Now, we add up this equation to the 1st equation given to eliminate y and solve for x. Shown below:

$1.2x+2.4y=-18\\4.8x-2.4y=-36\\---------\\6x=-54\\x=-9$

So, we have the value of x to be -9

Now, we substitute this value in 1st equation and solve for y:

$1.2x+2.4y=-18\\1.2(-9)+2.4y=-18\\-10.8+2.4y=-18\\2.4y=-7.2\\y=-3$

The value of y is -3

So,

x = -9

y = -3

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10.5% of the population is 65 or older. Find the probability that the following number of persons selected at random from 25 peo

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Given:

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1 year ago

The graph below shows the solution to which system of inequalities?

nlexa [21]

Answer:

Option D.

Step-by-step explanation:

Consider option D. $y\leq \frac{3x}{4}+10\,,\,y\leq \frac{-x}{2}-3$

Take point (0,0)

On putting this point in inequation $y\leq \frac{3x}{4}+10$ , we get

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