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4 years ago

X=-2y-1 and 4x-4y=20 equals what ordered pair

Mathematics

1 answer:

Margarita [4]4 years ago

3 0

Answer:

B), x=-1, y=-2, z=1.

Step-by-step explanation:

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Kyree paid $10 for a pizza he now has $46.how much money did he have before buying the pizza ??

Taya2010 [7]

46 + 10 = 56

5 0

3 years ago

Read 2 more answers

The sum of the three numbers is 180. The first number is 10 more than the mean of the three numbers and the second number is 4 l

4vir4ik [10]

Answer:

The third number (c) is 54.

The other ones are 70 and 56.

Step-by-step explanation:

We have 3 numbers, let's call them a, b and c.

We know that the sum of the three numbers is 180, thus:

$a+b+c=180$

We also know that the first number is 10 more than the mean of the three numbers <em>(Note: the mean is the sum of the numbers divided by the number of numbers).</em> Thus:

$a=\frac{a+b+c}{3} +10\\a=\frac{a+b+c+30}{3} \\3a=a+b+c+30\\2a=b+c+30$

Finally the second number is 4 less than the mean:

$b=\frac{a+b+c}{3}-4\\b=\frac{a+b+c-12}{3} \\3b=a+b+c-12\\2b=a+c-12$

Now we have our set of equations and we can proceed to solve them:

$a+b+c=180\\2a=b+c+30\\2b=a+c-12$

Solving for a in our first equation we have: $a=180-b-c$ and substituting this in our second equation we have:

$2a=b+c+30\\2(180-b-c)=b+c+30\\360-2b-2c=b+c+30\\330=3b+3c\\110=b+c$

Now taking this last result into our first equation we have:

$a+b+c=180\\a+(b+c)=180\\a+110=180\\a=70$

Now we are going to solve for b in our second equation and substitute this in our third equation: $b= 180-a-c$

$2b=a+c-12\\2(180-a-c)=a+c-12\\360-2a-2c=a+c-12\\372=3a+3c\\124=a+c$

But we know that a =70, so we can substitute it in our last line:

$124=a+c\\124=70+c\\54=c$

Now we just need to find b and we can use our first original equation to do this:

$a+b+c=180\\70+b+54=180\\124+b=180\\b=180-124\\b=56$

8 0

4 years ago

Use the definition to complete the biconditional statement.

ICE Princess25 [194]

The given information as "An equilateral triangle has three congruent sides"

An equilateral triangle is a triangle in which all three sides are equal

The equilateral triangles are also equiangular

That is, all three internal angles are also congruent to each other.

Thus the triangle is equilateral then

"IF AND ONLY IF IT HAS THREE CONGRUENT SIDES".

4 0

3 years ago

I’ll mark brainliest

Whitepunk [10]

Answer:

x ≤ 10

Step-by-step explanation:

The sign that I used means less than or equal to. So that means that there can either be 10 people exactly, or less than 10 people.

6 0

3 years ago

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2b + 9 when b = 3 I Really need help in math

Allisa [31]

Step-by-step explanation:

=2b+9

=2×3+9

=6+9

=15

hope it helps.

8 0

3 years ago