Question

SYSTEM OF LINNEAR EQUATIONS!

Answer 1

Answer:

Step-by-step explanation:

2x+3y=15

x-3y=18

------------------

x=3y+18

2(3y+18)+3y=15

6y+36+3y=15

9y=15-36

9y=-21

y=-21/9

simplify

y=-7/3

x-3(-7/3)=18

x+7=18

x=18-7

x=11

Answer: x=11, y=-7/3. (11, -7/3).

---------------------------------------------

2x+3y=20

-2x+y=20

----------------

4y=40

y=40/4

y=10

2x+3(10)=20

2x+30=20

2x=20-30

2x=-10

x=-10/2

x=-5

Answer: x=-5, y=10. (-5, 10).

-------------------------------------------

3x-4y=-5

-10x+4y=12

--------------------

-7x=7

x=7/-7

x=-1

3(-1)-4y=-5

-3-4y=-5

4y=-3-(-5)

4y=-3+5

4y=2

y=2/4

simplify

y=1/2

Answer: x=-1, y=1/2. (-1, 1/2).