How do u slove systems by elemination -12x+6y=18 6x-7y=-5

2 answers:

8 0

-12x+6y=18 First line up the two equations
6x-7y=-5
-12x+6y=18
12x-14y=-10 Then find common factor and multiply one of the variables.
-8y=8Next eliminate the x and solve for y by dividing -8 on both sides getting
y=-1
Lastly plug in y into one of the original equations and solve for x
Check your answer by plugging into the original equation

vitfil [10]3 years ago

6 0

You need to add one equation to the other. To do this, multiply the divide the entire equation by 2. The resulting equation gives: -6x + 3y = 9
Now, add this to the second. Doing this will cancel out the 6xs because they are opposite signs.
-4y = 4 is your simplified equation.
Solve for y: y = -1
Plug this into an original equation.
-12x + 6(-1) = 18
-12x -6 = 18
-12x = 24
x = -2

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A stadium brings in 16.25 million per year. It pays football related expenses of 13.5 million and stadium expenses of 2.7 millio

Alexxx [7]

Answer:

Option C) $50,000

Step-by-step explanation:

We are given the following in the question:

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Profit earned by stadium =

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Thus, the correct answer is

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Pyramid A has height 5 1/2, and Pyramid B has height 2 3/4. A and B are similar. What is the ratio of their:

N76 [4]

Answer:

Lateral areas have ratio of 4:1

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Step-by-step explanation:

There is a rule in 3D geometry that when two solids are similar, and their edges are in the ratio of $a:b$ , the ratio of any surface area type measure is always $a^2:b^2$ this includes the lateral area, which is just a surface area minus the base, which is not important for this problem. The ratio of volumes of those similar solids is in the ratio of $a^3:b^3\\$ .

Now, to solve this, we need to find the ratio of any corresponding length of these similar pyramids. We have both the heights, so if we form a ratio of $\frac{5\frac{1}{2} }{2\frac{3}{4} }$ which if you simplify it, it is $\frac{5.5}{2.75}$ , which is $2$ . The ratio of the heights are $2:1$ .

Now we can apply those rules to this ratio, the ratio of lateral areas would then be $2^2:1^2$ , which is $4:1$ . the ratio of volumes would be $2^3:1^3$ , which is $8:1$