A board is 24 in. long. find all the whole number lengths into which it can be evenly divided.

For which system of equations is (5, 3) the solution? A. 3x – 2y = 9 3x + 2y = 14 B. x – y = –2 4x – 3y = 11 C. –2x – y = –13 x

Alla [95]

The correct answer is:

D) $\left \{ {{2x-y=7} \atop {2x+7y=31}} \right.$ .

Explanation:

We solve each system to find the correct answer.

For A:
$\left \{ {{3x-2y=9} \atop {3x+2y=14}} \right.$

Since we have the coefficients of both variables the same, we will use elimination to solve this.

Since the coefficients of y are -2 and 2, we can add the equations to solve, since -2+2=0 and cancels the y variable:
$\left \{ {{3x-2y=9} \atop {+(3x+2y=14)}} \right. 
\\
\\6x=23$

Next we divide both sides by 6:
6x/6 = 23/6
x = 23/6

This is not the x-coordinate of the answer we are looking for, so A is not correct.

For B:
$\left \{ {{x-y=-2} \atop {4x-3y=11}} \right.$

For this equation, it will be easier to isolate a variable and use substitution, since the coefficient of both x and y in the first equation is 1:
x-y=-2

Add y to both sides:
x-y+y=-2+y
x=-2+y

We now substitute this in place of x in the second equation:
4x-3y=11
4(-2+y)-3y=11

Using the distributive property, we have:
4(-2)+4(y)-3y=11
-8+4y-3y=11

Combining like terms, we have:
-8+y=11

Add 8 to each side:
-8+y+8=11+8
y=19

This is not the y-coordinate of the answer we're looking for, so B is not correct.

For C:
Since the coefficient of x in the second equation is 1, we will use substitution again.

x+2y=-11

To isolate x, subtract 2y from each side:
x+2y-2y=-11-2y
x=-11-2y

Now substitute this in place of x in the first equation:
-2x-y=-13
-2(-11-2y)-y=-13

Using the distributive property, we have:
-2(-11)-2(-2y)-y=-13
22+4y-y=-13

Combining like terms:
22+3y=-13

Subtract 22 from each side:
22+3y-22=-13-22
3y=-35

Divide both sides by 3:
3y/3 = -35/3
y = -35/3

This is not the y-coordinate of the answer we're looking for, so C is not correct.

For D:
Since the coefficients of x are the same in each equation, we will use elimination. We have 2x in each equation; to eliminate this, we will subtract, since 2x-2x=0:

$\left \{ {{2x-y=7} \atop {-(2x+7y=31)}} \right. 
\\
\\-8y=-24$

Divide both sides by -8:
-8y/-8 = -24/-8
y=3

The y-coordinate is correct; next we check the x-coordinate Substitute the value for y into the first equation:
2x-y=7
2x-3=7

Add 3 to each side:
2x-3+3=7+3
2x=10

Divide each side by 2:
2x/2=10/2
x=5

This gives us the x- and y-coordinate we need, so D is the correct answer.

7 0

3 years ago

Which best describes the range of a function?

MArishka [77]

Answer:

C, the set of all possible output values

Step-by-step explanation:

Range = Output

8 0

3 years ago

Read 2 more answers

Round 9.24 to nearest hundrer

Elanso [62]

Answer:

9.24

Step-by-step explanation:

Integer Part: 9

Fractional Part: 240

If the last digit in the fractional part of 9.240 is less than 5, then simply remove the last the digit of the fractional part.

So 9.24 rounded to the nearest hundredth is:

9.24

4 0

3 years ago

Please help me out with this

Tanya [424]

Answer:

up is equal to 5/ 6

left side is equal to 3/4

Step-by-step explanation:

1/6 + 1/6+ 1/6+ 1/6+ 1/6= 5/6

1/4 + 1/4 + 1/4= 3/4

6 0

3 years ago

A cosmetic factory has 630 employees.

OleMash [197]

Answer:

The answer is 210 men work at the factory and 410 woman work at the factory.

Step-by-step explanation:

Because 630 divided by 3 is 210, so 210 multiplyed by 2 get you 420 which 2/3 of the employees that are woman so 210 men work at the factory.

:)

5 0

3 years ago

Read 2 more answers