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HELP ASAP PLZZZZ

Solve the following system of equations by linear combination: 3d – e = 7 d + e = 5

There is no solution. The solution is (2, –1). There are an infinite number of solutions. The solution is (3, 2). 1 points

QUESTION 2 Solve, using linear combination. 4x + y = 5 3x + y = 3

(0, –3) (0, 5) (–3, 7) (2, –3)
QUESTION 3 Solve using linear combination. a – 2b = –2 2a + 2b = 14

Which ordered pair in the form (a, b) is the solution to the system of equations?

(4, 3) (3, 4) (1, 6) (5, 3) 1 points

QUESTION 4 Solve, using linear combination. 11x + 4y = 18 3x + 4y = 2

(2, 0) (4, –5) (2, 1) (2, –1) 1 points

QUESTION 5 Solve the following system of equations by linear combination:

2d + e = 8 d – e = 4 There is no solution. The solution is (5, –2). There are an infinite number of solutions. The solution is (4, 0).'

User Shante
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1 Answer

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QUESTION 1

The given system of equations is


3d - e = 7...eqn(1)

d + e = 5...eqn(2)

To solve by linear combination, we add equation (1) to equation (2) to get,


3d + d= 7 + 5



4d = 12


We divide through by 4 to obtain,



d = (12)/(4)



d = 3


We put d=3 into equation (2) to get,




3+ e = 5



e = 5 - 3



e = 2



\boxed {The \: solution \: is \: (3, 2)}



QUESTION 2


The given system is

4x + y = 5 ...eqn(1)

3x + y = 3 ...eqn(2)


To solve by linear combination, we subtract equation (2) from equation (1) to eliminate y from the equation.

This will give us,


4x - 3x = 5 - 3



This implies that,


x = 2


Put x=3 into equation (1) to get,


4(2) + y = 5


8+ y = 5



y = 5 - 8




y = - 3

The solution is


(2,-3)



QUESTION 3

We want to solve the system;


a – 2b = –2 ....eqn(1)


2a + 2b = 14...eqn(2)

by linear combination.


We need to add equation (1) to equation (2) to eliminate b.


This implies that,


2a + a = 14 + - 2




Simplify,


3a = 12



Divide both sides by 3 to get,



a = 4
Put a=4 into equation (2) to obtain,




2(4) + 2b = 14



8 + 2b = 14

2b = 14 - 8



2b = 6



b = 3


The ordered pair in the form (a, b) is


(4,3)



QUESTION 4

The given system of equations is


11x + 4y = 18 ...eqn(1)

3x + 4y = 2 ...eqn(2)


We subtract equation (2) from equation (1) to get,



11x - 3x = 18 - 2



8x = 16



x = 2


Put x=2 into equation (2) to obtain,



3(2) + 4y = 2


This implies that,



6 + 4y = 2



4y = 2 - 6



4y = - 4



y=-1

The correct answer is (2,-1).




QUESTION 5

The given system is ;

2d + e = 8...eqn1

d – e = 4...eqn2


We add the two equations to eliminate e.


This implies that,


2d + d = 8 + 4



3d = 12



We divide both sides by 3 to get,



d = 4


We put d=4 into equation (2) to get,


4 - e = 4


- e = 4 - 4




- e = 0




e = 0


The solution is


(4,0)
User Hemanth
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8.3k points