Question

what is the number of solutions to the system?

x + y = -1
5x - 5y = 7

Answer 1

someone please help me! i dont get this

Answer 2

solve for x then plug it in the second equation

Answer 3

so i would set it up like x + y = -1 = 5x - 5y = 7 ?

Answer 4

x = -1 - y
5(-1 - y) -5y = 7

then you'll know what y is

Answer 5

if you know y then you can plug in y to first equation and find out what x is

Answer 6

wait let me write this down and try to do that

Answer 7

-5 - 5y -5y = 7
-10y = 14
y = -14/10

Answer 8

when you have two unknown (here x and y) then you always want to solve for x or y, then plug it into the other equation so you're working with just one unknown variable

Answer 9

ok i get the -10 y part. buy what about the -5 and where did 14 come from?

Answer 10

ahhh. isee.

Answer 11

you try to get y on left and everything else on right

Answer 12

yeah but you left -5 out. what did you do with it? and where did 14 come from?

Answer 13

you move -5 to right side of = sign

Answer 14

you want to get rid of -5 on left side so you add +5 to both side

Answer 15

so -5 disappears on left and +5 appears on right

Answer 16

Okay. but that equals 12.

Answer 17

whatever you do on left you MUST do same on right to keep equation same

Answer 18

sorry it's 12 :)

Answer 19

12/10

Answer 20

i know that. ahh seee. thaats why i was like huh? lol

Answer 21

u got me confused rii there. its cool tho

Answer 22

so plug in y= -12/10 to find x

Answer 23

isnt it 12/-10 ?

Answer 24

it doesn't matter if it's on top or bottom

Answer 25

it's (-1) (12/10)

Answer 26

^^ that's the correct form

Answer 27

ahhhhh i seee. so the answer is one solution.

Answer 28

there's only one solution for y and one for x

Answer 29

answer is a fraction

Answer 30

i know. but its asking me how many solutions. one two or no solutions

Answer 31

i have this other one. i have to find the ordered pairs. let me see if i can do it.

-3x + 5y = 4
5x +5y = 60

Answer 32

i'm not sure what the question is asking?

Answer 33

there can be infinite combination of x and y and it'll give you those answers

Answer 34

it says give the ordered pairs that satisfies the system of equations

Answer 35

well for the other one that your talking about.... it was asking WHAT IS THE NUMBER OF SOLUTIONS TO THE SYSTEM? and i put ONE SOLUTION

Answer 36

theres another choice that says INFINITELY MANY SOLUTIONS

Answer 37

i think it may be asking for just x and y like (x, y)

Answer 38

so just one solution

Answer 39

yeah it is.

Answer 40

Okay. thanks.

Answer 41

let me see if i can do the other one.

Answer 42

i have a question

Answer 43

i did 5x ( -3x + 5y ) +5y = 60

Answer 44

no you have to solve for y first

Answer 45

y = (1/5)(3x +4)

Answer 46

then you plug it in like you did

Answer 47

so thats how im suppose set it up rii?

Answer 48

i'm not sure what you did

Answer 49

you first either solve for x or y

Answer 50

then plug in the result to the second equation

Answer 51

i want to solve for X

Answer 52

so how do i set it up?

Answer 53

x = (5y - 4)(1/3)

Answer 54

5[(5y - 4)(1/3)] +5y = 60

the bracket [ ] is the x

Answer 55

now you only have one variable y in your equation since we plugged in for x

Answer 56

where did one third come from?

Answer 57

wait let me get this straightt....

Answer 58

i just plugged in for x

Answer 59

ahh okay

Answer 60

so now that we have our equation we have to distribute the 5 to the perenthesis (5y-4) correct?

Answer 61

you can do that then divide everything by 3

Answer 62

i can distribute 5 to 1/3 righT?

Answer 63

i can distribute 5 to 1/3 righT?

Answer 64

i can distribute 5 to 1/3 righT?

Answer 65

i can distribute 5 to 1/3 righT?

Answer 66

i can distribute 5 to 1/3 righT?

Answer 67

i can distribute 5 to 1/3 righT?

Answer 68

i can distribute 5 to 1/3 righT?

Answer 69

i can distribute 5 to 1/3 righT?

Answer 70

i can distribute 5 to 1/3 righT?

Answer 71

you're not distributing since (1/3) is its own. you simply multiply

Answer 72

srry about that

Answer 73

so what i shud have is [ (25y-20) (1/3) ]

Answer 74

[ (25y-20) (1/3) ] + 5y = 60

Answer 75

yeah then solve for y

Answer 76

now you have to distribute (1/3)

Answer 77

im a little confused. so right this is what i have......
[ (25y-20) (1/3) ] + 5y = 60
-5y - 5y

[ (20y- 20) (1/3) ] = 60

Answer 78

no

Answer 79

you don't want to move 5y to other side because you still have 25y

Answer 80

you want to move 20(1/3) to right

Answer 81

then combine 25y(1/3) + 5y

Answer 82

you may want to use calculator

Answer 83

so multiply -20/2 times 1/3

Answer 84

remember we're trying to solve for y

Answer 85

wait ignore that.. typo

Answer 86

so multiply 20/1 times 1/3 then combien 25y times 1/3 + 5y then combine like terms so you'd end up with 30y (1/3)

Answer 87

no

Answer 88

you first distribute (1/3) to 25y and -20

Answer 89

so it's 25y(1/3) + 5y = 60 + 20(1/3)

Answer 90

y(25(1/3) + 5) = 60 + 20(1/3)

y = 60 + 20(1/3) / (25(1/3) + 5)

Answer 91

it looks real messy b/c i didn't simplify anything

Answer 92

\[y = 60 + 20(1/3)\div (25(1/3) + 5)\]

Answer 93

so now im gunna distribute 20 (1/3) and 25 (1/3)

Answer 94

no you just multiply

Answer 95

it's just 20/3 and 25/3

Answer 96

you can multiply by (1/3) or just divide by 3

Answer 97

500\3

Answer 98

where'd that come from