Ireally need

4. which ordered pair is a solution to the system of equations? use any method to solve.
2x - y = 5
3x + 2y = 4

a. (5,5)
b. (0,2)
c. (2,-1)
d. (-1,-7)

12. what is the solution to the system of equations? use the linear combination method.

3x+2y=7
5x-4y=19

a. there are an infinite number of solutions.
b. the solution is (3,-1).
c. there is no solution.
d. the solution is (5, 1).

no 4.

using substitution method

2x - y = 5...(i)

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

making y subject of formula in (i)

2x-y=5

2x-5=y

substitute y in (ii)

3x+2(2x-5)=4

opening bracket

3x+4x-10=4

collecting like terms

3x+4x=4+10

7x=14

dividing both sides by 7

7x/7=14/7

x=2.

but y=2x-5

y=2(2)-5

y=-1.

solution=(2,-1)

3x+2y=7...(i)

5x-4y=19...(ii)

multiply (i) by 2 and (ii) by 1

3x+2y=7}×2

5x-4y=19}×1

we get;

6x+4y=14

5x-4y=19

adding the two equations,

6x+5x=11x

4y+-4y=0

14+19=33

new equation

11x=33

divide both sides by 11

11x/11=33/11

x=3

replacing x in (i)

3x+2y=14

3(3)+2y=14

9+2y=14

2y=14-9

dividing both sides by 2

2y/2=5/2

y=5/2 or 2.5

solution=(3,5/2) which is not in the choices.

i think it is everything has to equal 180 so, if i correct 4=c. 6=d. 8=a. 7=b. and the last question would be c. because they are parallel lines and they are congruent.

step-by-step explanation:

the reason everything has to equal to 180 is because that is how it works. i'm guessing that is its rule. 4 and 8 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 6 and 7 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 60+60 is 180. so, now you have your answer