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3 years ago

If y = 2x and 3x - 3y = 2, then x =

Mathematics

1 answer:

faltersainse [42]3 years ago

5 0

Answer:

The value of x is equal to -2/3.

Step-by-step explanation:

In the problem it says that y equals 2x, and that 3x - 3y = 2.

The first step is to substitute 2x into y.

3x - 3(2x) = 2.

The next step is to use distributive property.

-3(2x) = -6x.

Now we need to add like terms.

3x - 6x = -3x.

Which gives us the equation -3x = 2.

The final step is to divide on both sides to get the value of x.

-3x/-3 = 2/-3.

x = -2/3.

So as you can see, x is equal to -2/3.

We can also check to make sure by redoing the problem, but substituting the value of x.

3(-2/3) - 3(2 * -2/3) = 2.

-2 - 3 * -4/3 = 2.

-2 + 4 = 2.

2 = 2.

The value of x is indeed -2/3.

You might be interested in

Two numbers multiply to be -7 and add to be -6. What are the numbers? Example; 2,3

rewona [7]

Given:

Let the two numbers be x and y.

Two numbers multiply to be -7 and add to be -6.

This can be written in equation as,

$xy=-7$ and

$x+y=-6$

Value of the two numbers:

Let us determine the value of the two numbers using substitution method.

Substituting $y=-6-x$ in the equation $xy=-7$ , we get;

$x(-6-x)=-7$

Simplifying, we get;

$-6x-x^2=-7$

$x^2+6x-7=0$

$(x+7)(x-1)=0$

$x=-7, 1$

Thus, the values of x are x = 1,-7

When x = 1 , the equation $x+y=-6$ becomes $y=-7$

When x = -7, the equation $x+y=-6$ becomes $y=1$

Therefore, the two numbers are 1 and -7

3 0

3 years ago

What is the average rate of change of f(x) = -x2 + 3x + 6 over the interval –3

Rufina [12.5K]

Answer:

$\frac{\Delta y}{\Delta x} =\frac{f(x_2)-f(x_1)}{x_2-x_1} =\frac{6-(-12)}{3-(-3)} =\frac{18}{6}= 3$

Step-by-step explanation:

To find the average rate of change of a function over a given interval, basically you need to find the slope. The mathematical definition of the slope is very similar to the one we use every day. In mathematics, the slope is the relationship between the vertical and horizontal changes between two points on a surface or a line. In this sense, the slope can be found using the following expression:

$Average\hspace{3}rate\hspace{3}of\hspace{3}change=Slope=\frac{y_2-y_1}{x_2-x_1} =\frac{f(x_2)-f(x_1)}{x_2-x_1}$