Question

solve x+2y=2, 5x+3y=-18

Answer 1

solve your first equation for x

Answer 2

do you know how to do this @jasco29645 ?

Answer 3

sure dont..i'm new at algebra

Answer 4

ok well start by subtracting 2y from both sides of the first equation. what do you get?

Answer 5

0

Answer 6

you would get x=-2y+2 correct?

Answer 7

yes

Answer 8

so take that and substitute it for x in the second equation, what would that look like?

Answer 9

5(0)+3y=-18

Answer 10

where are you getting 0 from?

Answer 11

you said to substitiute my previous answer for x for the 2nd equation

Answer 12

i meant the equation that i gave you sorry

Answer 13

0=-2y+2

Answer 14

instead of 0 use x
x=-2y+2

Answer 15

now if x=-2y+2 then you can plug in 5(-2y+2)+3y=-18 instead of 5x+3y=-18

Answer 16

you following me so far?

Answer 17

yes

Answer 18

do you know what the distributive property is?

Answer 19

yes...so 3x/3=-18/3 so x=-6

Answer 20

so now solve for y

Answer 21

no the distributive property is x(a+b)=xa+xb

Answer 22

5(-2y+2)+3y=-18 so with the distributive property we get -2y(5)+2(5)+3y=-18

Answer 23

so what does that simplify too?

Answer 24

-6

Answer 25

how did you get that?

Answer 26

because the -2y(5)=2(5) cancels out + 3==18 divided by 3 = - 6

Answer 27

no you cant cancel out unlike terms you would get -10y+10+3y=-18

Answer 28

so when you add like terms you get all the y's to one side and the other numbers to the other

Answer 29

so -10y+3y=-7

Answer 30

no you need to subtract 10 to both sides so you would get -10y+3y=-18-10

Answer 31

so add -10y+3y, and add up -18-10

Answer 32

-4

Answer 33

oops not negative..just 4

Answer 34

-7y=-28 divide both sides by -7 and you get
y=4

Answer 35

you cant just forget about the y

Answer 36

now that we have the y plug that back into the equation 5x+3y=-18

Answer 37

so what would our first step be?

Answer 38

@jasco29645 ?