Question

Which equation is in standard form & represents a line with slope -1 through the point (-3, 5)?
A) -x + y = 5
B) y = -x + 5
C) x + y = 2
D) y = -x + 2

Answer 1

A) y = x + 5 (does not have slope -1, can be eliminated)
B) y = -x + 5 (has slope -1)
C) y = -x + 2 (has slope -1)
D) y = -x + 2 (same eq as eq C) )

Answer 2

Test point (-3, 5) in equations B, C, and D.
Also, what does your textbook consider standard form for a linear equation?

Answer 3

you can use the point slope equation again

(y-y1) = m(x-x1)

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

y-5 = -x-3

slope-intercept form
y = -x +2

standard form
x+y = 2

Answer 4

@tanner23456 Okay, so the answer is C because they ask for standard form. Could you help me with a few more??

Answer 5

yeah, no worries

Answer 6

Do you want me to post them here or on another post?

Answer 7

I don't care. Whatever you want

Answer 8

A sapling, or young tree, is planted in a garden. After 3 years, it is 180 cm tall. After 7 years, it is 368 cm tall. How tall will the tree be after 10 years?
A) 587 cm
B) 509 cm
C) 470 cm
D) 548 cm

Answer 9

you could set up and equation something like this

y = mx +b

x = number of years

y = height

first we need to find the slope

(y2-y1)/(x2-x1)

(368-180)/(7-3)

188/4

m = 47

since the tree's height starts at zero the y-intercept is 0
y= 47x

now plug in x

y=47(10)

y=470

Answer 10

Thank you :)

Answer 11

An empty 6-gal water jug weighs 0.5 lb. With 3 c of water inside, the jug weighs 2 lb. Which equation models the jug's weight y when it contains x cups of water?
A) y = 0.5x - 0.5
B) y = -0.5x - 0.5
C) y = 0.5x + 0.5
D) y = -0.5x + 0.5

Answer 12

same type of thing.

x= cups of water

y= weight

find the slope

(y2-y1)/(x2-x1)

(2-0.5)/(3-0)

1.5/3

slope = 0.5

this time the weight starts at 0.5 when x=0 so the y-intercept will be 0.5

y= 0.5x + 0.5

Answer 13

What is the slope for the equation y = 7?
A) 0
B) -7
C) Undefined
D) 7

Answer 14

If you think about it on the graph y=7 would look something like this.



therefore the slope is 0