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A system of equations is shown below:

n = 3m + 7
n − 2m = 1

What is the solution, in the form (m, n), to the system of equations?

(3, 7)
(1, 8)
(−3, −2)
(−6, −11)


Which statement is true about the solutions for the equation 4y + 6 = −2?

It has infinitely many solutions.
It has two solutions.
It has one solution.
It has no solution.


The system of equations shown below is graphed on a coordinate grid:

3y + x = 4
2y − x = 6

Which statement is true about the coordinates of the point that is the solution to the system of equations?

It is (−2, 2) and lies on both lines.
It is (−5, 3) and lies on both lines.
It is (−5, 3) and does not lie on either line.
It is (−2, 2) and does not lie on either line.


What is the value of z in the equation 2z + 6 = −4?

5
1
−1
−5


Which statement is true for the equation 2x − 2x − 7 = −7?

It has infinitely many solutions.
It has two solutions.
It has one solution.
It has no solution.


The incomplete work of a student to solve an equation is shown below:

Step 1: 4x + 12 = 4
Step 2: ?
Step 3: x = −8 ÷ 4
Step 4: x = −2

What is the missing Step 2?

4x = 8
4x = 16
4x = −16
4x = −8



Which set of steps shows the solution to the equation 2y = −8?

y = −8 − 2; y = 6
y = −8 ÷ (−2); y = 4
y = −8 ÷ 2; y = −4
y = −8 − (−2); y = −6



A system of two equations is shown below:

Equation C: a = 3b + 6
Equation D: a = 7b − 1

What value of a can be substituted into equation D to solve the system of equations?

3b
7b
3b + 6
7b − 1

User Kkkev
by
8.6k points

1 Answer

7 votes

Answer:

1. (-6, -11)

2. It has one solution

3. It is (−2, 2) and lies on both lines

4.
-5

5. It has infinitely many solutions.

6.
4x=-8

7. y = −8 ÷ 2; y = −4

8. 3b + 6


Explanation:


Question 1:

Substituting equation 1 into equation 2 and solving for
m gives us:


n-2m=1\\(3m+7)-2m=1\\m+7=1\\m=1-7\\m=-6

Plugging this value into equation 1 gives us
n, so we have:


n=3m+7\\n=3(-6)+7\\n=-18+7\\n=-11

Hence, the solution, in the form (m, n), to the system of equations is (-6,-11).


Question 2:

Solving the equation for
y gives us:


4y+6=-2\\4y=-2-6\\4y=-8\\y=(-8)/(4)=-2

As we can see, there is only one solution.


Question 3:

We can add the both equations so
x cancels out and then we can solve for
y:


(3y+x=4)\\+(2y-x=6)\\---------\\5y=10\\y=(10)/(5)=2

Substituting this value of
y into any equation above (let's use equation 1) will give us
x:


3y+x=4\\3(2)+x=4\\6+x=4\\x=4-6\\x=-2

So the intersection point (or solution) (-2, 2) lies on both the lines.


Question 4:

Let's do some algebra and figure out the value of
z:


2z+6=-4\\2z=-4-6\\2z=-10\\z=(-10)/(2)=-5


z is -5


Question 5:

Reducing the equation gives us:


2x-2x-7=-7\\0-7=-7\\-7=-7

We can plug in ANY VALUE into
x and make this equation true. So there are INFINITELY MANY SOLUTIONS.


Question 6:

Step 2 of the solution should be taking 12 to the other side so that variable is on one side and all the numbers to the other. So 2nd step would be:


4x+12=4\\4x=4-12\\4x=-8

Rest of the steps follow. So, 2nd step would be
4x=-8.


Question 7:

The next step to solving this equation would be to DIVIDE -8 by 2 since 2 is multiplied with
y.


2y=-8\\y=(-8)/(2)=-4

Third answer choice is right.


Question 8:

We can substitute the value of
a given in Equation C into Equation D to solve the system of equations.

The value of
a in Equation C is given as
a=3b+6

Third answer choice is right.

User Yagnesh Dobariya
by
8.0k points