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2 years ago

Which ordered pairs in the form (x, y) are solutions to the equation 3x – 4y = 21? Choose all answers that are correct.

Mathematics

2 answers:

EleoNora [17]2 years ago

6 0

<h2>Answer:</h2>

The ordered pair which are solution to the equation are:

B. (-1,-6)

C. (7,0)

D. (11,3)

<h2>Step-by-step explanation:</h2>

We are given a equation in terms of variables x and y as follows:

$3x-4y=21$

The ordered pair which are solutions to the equation are the points which when substituted to the equation satisfies the equation.

(-3,3)

i.e. we put x= -3 and y=3 we get:

$3\times (-3)-4\times 3=21\\\\i.e.\\\\-9-12=21\\\\i.e.\\\\-21=21$

which is not possible.

Hence, (-3,3) is not a solution to the equation.

(-1,-6)

we put x=-1 and y=-6 into the equation to get:

$3\times -1-4\times (-6)=21\\\\i.e.\\\\-3+24=21\\\\i.e.\\\\21=21$

Hence, (-1,-6) is a solution to the equation.

(7,0)

we put x=7 and y=0 in the equation.

i.e.

$3\times 7-4\times 0=21\\\\i.e.\\\\21-0=21\\\\i.e.\\\\21=21$

Hence, (7,0) is a solution to the equation.

(11,3)

we put x=11 and y=3 into the equation.

i.e.

$3\times 11-4\times 3=21\\\\i.e.\\\\33-12=21\\\\i.e.\\\\21=21$

Hence, (11,3) is a solution to the equation.

bekas [8.4K]2 years ago

5 0

A. (−3, 3)
<span>3x – 4y = 21
</span>3(-3) - 4(3) = 21
-21 = 21 >>>>> not equal

B. (−1, −6)
<span>3(-1) - 4(-6) = 21
</span>21 = 21 >>>>>>>>>>Equal

C. (7, 0)
<span>3(7) - 4(0) = 21
</span>21 = 21>>>>>>>>>>equal

D. (11, 3)
<span>3(11) - 4(3) = 21
</span>21 = 21 >>>>>>>>>equal

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lyudmila [28]

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3 years ago

Read 2 more answers

analyze this situation and determine how much cookie dough is "wasted" when 3-inch cookies are cut. then have each team member c

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Answer:

The result is the same.

Step-by-step explanation:

I think your question is missed of key information, allow me to add in and hope it will fit the original one.

Please have a look at the attached photo.

My answer:

Given the information:

square 12 inches wide
3-inch diameter cookies are cut => its radius is: 1.5 inches

Hence we can find some information:

The area of the square is: $12^{2} = 144$ square inches
The area of a cookies is: $r^{2}$ π = 3.14* $1.5^{2}$ = 7.065 square inches
The total number of 3-inch cookies are: 4*4 =16

=> The total area of the cookies is: 16* 7.065 = 113.04 square inches

=> how much cookie dough is "wasted" when 3-inch cookies are cut:

= The area of the square - The total area of the cookies

= 144 - 113.04 = 30.96 square inches

If the diameter is increased to 4 inches => its radius: 2 inches, we have:

The area of a cookies is: $r^{2}$ π = $2^{2} *3.14 = 12.56$ square inches
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=> The total area of the cookies is: 9* 12.56 = 113.04 square inches

=> how much cookie dough is "wasted" when 4-inch cookies are cut:

= The area of the square - The total area of the cookies

= 144 - 113.04 = 30.96 square inches

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3 years ago

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s2008m [1.1K]

Answer:

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3 years ago

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