Question

For which of the following systems of linear equations is the ordered pair negative one comma seven a solution?

x minus four y equals one…two x minus three y equals eleven

x plus two y equals five…x plus three y equals four

x minus five y equals negative two…three x plus nine y equals twelve

y equals eight plus x…x plus two y equals thirteen

Answer 1

we need to sub (-1,7) into your answer choices and see which is correct
x - 4y = 1
-1 - 4(7) = 1
-1 - 28 = -1
-29 = -1 (not this one)
we do not need to try the other equation because they both have to be true.

x + 2y = 5
-1 + 2(7) = 5
-1 + 14 = 5
13 = 5 (not this one)

x - 5y = -2
-1 - 5(7) = -2
-1 - 35 = -2
-36 = -2 (nope)

y = 8 + x
7 = 8 + (-1)
7 = 8 - 1
7 = 7 (correct)
now we will try the other equation
x + 2y = 13
-1 + 2(7) = 13
-1 + 14 = 13
13 = 13 (correct)
It is the last answer choice because (-1,7) satisfies both equations

Answer 2

Ok, :) I did one just similar to this could you check my answer ?

Answer 3

of course

Answer 4

A first grade class has 6-year olds and 7-year olds. There are 13 children in the class, and the total of their ages is 83. Which system of linear equations represents the problem?

seven x plus six y equals thirteen x plus y equals eighty-three

six x plus seven y equals eighty-three x plus y equals thirteen x

six x plus seven y equals thirteen x plus y equals eighty-three x

seven x plus six y equals eighty-three x plus y equals thirteen

I said it was "B" Am i right? iF I'm not it's opition D i think ?

Answer 5

lets try B
6x + 7y = 83
x + y = 13x ----not this one....there is not supposed to be an x after 13

lets try D
7x + 6y = 83
x + y = 13 (this is correct)
answer is D.

Answer 6

Okay thank you ! :)

Answer 7

sure :)

Answer 8

I have one more i neeed you to check

Answer 9

lets see it

Answer 10

Lines A and B form a linear system. Line A has an undefined slope and an x-intercept of (6, 0). Line B also has an undefined slope and has an x-intercept of (-4, 0). How are these lines characterized?

parallel

intersecting

coincidental

not enough information

I said B

Answer 11

when the slope of the line is undefined, it is a vertical line. Is the slope undefined or is it 0 ?

Answer 12

Undefined

Answer 13

I am going to say parallel...but not 100% sure

Answer 14

oK :)